diff --git a/services/tests/servicestests/src/com/android/server/wm/AnimatingAppWindowTokenRegistryTest.java b/services/tests/servicestests/src/com/android/server/wm/AnimatingAppWindowTokenRegistryTest.java
index b5fe8b1..a907161 100644
--- a/services/tests/servicestests/src/com/android/server/wm/AnimatingAppWindowTokenRegistryTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/AnimatingAppWindowTokenRegistryTest.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -29,11 +29,9 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
@@ -41,12 +39,11 @@
  * Tests for the {@link TaskStack} class.
  *
  * Build/Install/Run:
- *  atest FrameworksServicesTests:com.android.server.wm.AnimatingAppWindowTokenRegistryTest
+ *  atest FrameworksServicesTests:AnimatingAppWindowTokenRegistryTest
  */
 @SmallTest
 @Presubmit
 @FlakyTest(detail = "Promote once confirmed non-flaky")
-@RunWith(AndroidJUnit4.class)
 public class AnimatingAppWindowTokenRegistryTest extends WindowTestsBase {
 
     @Mock
@@ -56,14 +53,14 @@
     Runnable mMockEndDeferFinishCallback1;
     @Mock
     Runnable mMockEndDeferFinishCallback2;
+
     @Before
     public void setUp() throws Exception {
-        super.setUp();
         MockitoAnnotations.initMocks(this);
     }
 
     @Test
-    public void testDeferring() throws Exception {
+    public void testDeferring() {
         final AppWindowToken window1 = createAppWindowToken(mDisplayContent,
                 WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD);
         final AppWindowToken window2 = createAppWindow(window1.getTask(), ACTIVITY_TYPE_STANDARD,
@@ -85,7 +82,7 @@
     }
 
     @Test
-    public void testContainerRemoved() throws Exception {
+    public void testContainerRemoved() {
         final AppWindowToken window1 = createAppWindowToken(mDisplayContent,
                 WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD);
         final AppWindowToken window2 = createAppWindow(window1.getTask(), ACTIVITY_TYPE_STANDARD,
diff --git a/services/tests/servicestests/src/com/android/server/wm/AppTransitionControllerTest.java b/services/tests/servicestests/src/com/android/server/wm/AppTransitionControllerTest.java
index fc3ca93..5e12a95 100644
--- a/services/tests/servicestests/src/com/android/server/wm/AppTransitionControllerTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/AppTransitionControllerTest.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -27,28 +27,28 @@
 import android.view.WindowManager;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
+/**
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:AppTransitionControllerTest
+ */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class AppTransitionControllerTest extends WindowTestsBase {
 
     private AppTransitionController mAppTransitionController;
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
-        mAppTransitionController = new AppTransitionController(sWm, mDisplayContent);
+        mAppTransitionController = new AppTransitionController(mWm, mDisplayContent);
     }
 
     @Test
-    public void testTranslucentOpen() throws Exception {
-        synchronized (sWm.mGlobalLock) {
+    public void testTranslucentOpen() {
+        synchronized (mWm.mGlobalLock) {
             final AppWindowToken behind = createAppWindowToken(mDisplayContent,
                     WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD);
             final AppWindowToken translucentOpening = createAppWindowToken(mDisplayContent,
@@ -64,8 +64,8 @@
     }
 
     @Test
-    public void testTranslucentClose() throws Exception {
-        synchronized (sWm.mGlobalLock) {
+    public void testTranslucentClose() {
+        synchronized (mWm.mGlobalLock) {
             final AppWindowToken behind = createAppWindowToken(mDisplayContent,
                     WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD);
             final AppWindowToken translucentClosing = createAppWindowToken(mDisplayContent,
diff --git a/services/tests/servicestests/src/com/android/server/wm/AppTransitionTests.java b/services/tests/servicestests/src/com/android/server/wm/AppTransitionTests.java
index ee6fbac..f12619c 100644
--- a/services/tests/servicestests/src/com/android/server/wm/AppTransitionTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/AppTransitionTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -32,81 +32,75 @@
 import static org.mockito.Mockito.doNothing;
 import static org.mockito.Mockito.spy;
 
-import android.content.Context;
 import android.graphics.Rect;
 import android.platform.test.annotations.Presubmit;
 import android.view.Display;
 import android.view.IApplicationToken;
 
-import androidx.test.InstrumentationRegistry;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Test class for {@link AppTransition}.
  *
- * atest AppTransitionTests
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:AppTransitionTests
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class AppTransitionTests extends WindowTestsBase {
 
     private DisplayContent mDc;
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
-        final Context context = InstrumentationRegistry.getTargetContext();
-        mDc = sWm.getDefaultDisplayContentLocked();
+        mDc = mWm.getDefaultDisplayContentLocked();
         // For unit test,  we don't need to test performSurfacePlacement to prevent some
         // abnormal interaction with surfaceflinger native side.
-        sWm.mRoot = spy(sWm.mRoot);
-        doNothing().when(sWm.mRoot).performSurfacePlacement(anyBoolean());
+        mWm.mRoot = spy(mWm.mRoot);
+        doNothing().when(mWm.mRoot).performSurfacePlacement(anyBoolean());
     }
 
     @Test
-    public void testKeyguardOverride() throws Exception {
-        sWm.prepareAppTransition(TRANSIT_ACTIVITY_OPEN, false /* alwaysKeepCurrent */);
-        sWm.prepareAppTransition(TRANSIT_KEYGUARD_GOING_AWAY, false /* alwaysKeepCurrent */);
+    public void testKeyguardOverride() {
+        mWm.prepareAppTransition(TRANSIT_ACTIVITY_OPEN, false /* alwaysKeepCurrent */);
+        mWm.prepareAppTransition(TRANSIT_KEYGUARD_GOING_AWAY, false /* alwaysKeepCurrent */);
         assertEquals(TRANSIT_KEYGUARD_GOING_AWAY, mDc.mAppTransition.getAppTransition());
     }
 
     @Test
-    public void testKeyguardKeep() throws Exception {
-        sWm.prepareAppTransition(TRANSIT_KEYGUARD_GOING_AWAY, false /* alwaysKeepCurrent */);
-        sWm.prepareAppTransition(TRANSIT_ACTIVITY_OPEN, false /* alwaysKeepCurrent */);
+    public void testKeyguardKeep() {
+        mWm.prepareAppTransition(TRANSIT_KEYGUARD_GOING_AWAY, false /* alwaysKeepCurrent */);
+        mWm.prepareAppTransition(TRANSIT_ACTIVITY_OPEN, false /* alwaysKeepCurrent */);
         assertEquals(TRANSIT_KEYGUARD_GOING_AWAY, mDc.mAppTransition.getAppTransition());
     }
 
     @Test
-    public void testForceOverride() throws Exception {
-        sWm.prepareAppTransition(TRANSIT_KEYGUARD_UNOCCLUDE, false /* alwaysKeepCurrent */);
+    public void testForceOverride() {
+        mWm.prepareAppTransition(TRANSIT_KEYGUARD_UNOCCLUDE, false /* alwaysKeepCurrent */);
         mDc.getController().prepareAppTransition(TRANSIT_ACTIVITY_OPEN,
                 false /* alwaysKeepCurrent */, 0 /* flags */, true /* forceOverride */);
         assertEquals(TRANSIT_ACTIVITY_OPEN, mDc.mAppTransition.getAppTransition());
     }
 
     @Test
-    public void testCrashing() throws Exception {
-        sWm.prepareAppTransition(TRANSIT_ACTIVITY_OPEN, false /* alwaysKeepCurrent */);
-        sWm.prepareAppTransition(TRANSIT_CRASHING_ACTIVITY_CLOSE, false /* alwaysKeepCurrent */);
+    public void testCrashing() {
+        mWm.prepareAppTransition(TRANSIT_ACTIVITY_OPEN, false /* alwaysKeepCurrent */);
+        mWm.prepareAppTransition(TRANSIT_CRASHING_ACTIVITY_CLOSE, false /* alwaysKeepCurrent */);
         assertEquals(TRANSIT_CRASHING_ACTIVITY_CLOSE, mDc.mAppTransition.getAppTransition());
     }
 
     @Test
-    public void testKeepKeyguard_withCrashing() throws Exception {
-        sWm.prepareAppTransition(TRANSIT_KEYGUARD_GOING_AWAY, false /* alwaysKeepCurrent */);
-        sWm.prepareAppTransition(TRANSIT_CRASHING_ACTIVITY_CLOSE, false /* alwaysKeepCurrent */);
+    public void testKeepKeyguard_withCrashing() {
+        mWm.prepareAppTransition(TRANSIT_KEYGUARD_GOING_AWAY, false /* alwaysKeepCurrent */);
+        mWm.prepareAppTransition(TRANSIT_CRASHING_ACTIVITY_CLOSE, false /* alwaysKeepCurrent */);
         assertEquals(TRANSIT_KEYGUARD_GOING_AWAY, mDc.mAppTransition.getAppTransition());
     }
 
     @Test
-    public void testAppTransitionStateForMultiDisplay() throws Exception {
+    public void testAppTransitionStateForMultiDisplay() {
         // Create 2 displays & presume both display the state is ON for ready to display & animate.
         final DisplayContent dc1 = createNewDisplayWithController(Display.STATE_ON);
         final DisplayContent dc2 = createNewDisplayWithController(Display.STATE_ON);
@@ -149,7 +143,7 @@
     }
 
     @Test
-    public void testCleanAppTransitionWhenTaskStackReparent() throws Exception {
+    public void testCleanAppTransitionWhenTaskStackReparent() {
         // Create 2 displays & presume both display the state is ON for ready to display & animate.
         final DisplayContent dc1 = createNewDisplayWithController(Display.STATE_ON);
         final DisplayContent dc2 = createNewDisplayWithController(Display.STATE_ON);
diff --git a/services/tests/servicestests/src/com/android/server/wm/AppWindowContainerControllerTests.java b/services/tests/servicestests/src/com/android/server/wm/AppWindowContainerControllerTests.java
index fcd8a39e4..415b5d9 100644
--- a/services/tests/servicestests/src/com/android/server/wm/AppWindowContainerControllerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/AppWindowContainerControllerTests.java
@@ -21,6 +21,8 @@
 import static android.content.res.Configuration.EMPTY;
 import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_STARTING;
 
+import static androidx.test.platform.app.InstrumentationRegistry.getInstrumentation;
+
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
@@ -29,10 +31,8 @@
 
 import android.platform.test.annotations.Presubmit;
 
-import androidx.test.InstrumentationRegistry;
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.wm.WindowTestUtils.TestTaskWindowContainerController;
 
@@ -41,16 +41,17 @@
 /**
  * Test class for {@link AppWindowContainerController}.
  *
- * atest FrameworksServicesTests:com.android.server.wm.AppWindowContainerControllerTests
+ * atest FrameworksServicesTests:AppWindowContainerControllerTests
  */
+@FlakyTest(bugId = 74078662)
 @SmallTest
 @Presubmit
-@FlakyTest(bugId = 74078662)
-@org.junit.runner.RunWith(AndroidJUnit4.class)
 public class AppWindowContainerControllerTests extends WindowTestsBase {
 
+    private final String mPackageName = getInstrumentation().getTargetContext().getPackageName();
+
     @Test
-    public void testRemoveContainer() throws Exception {
+    public void testRemoveContainer() {
         final WindowTestUtils.TestAppWindowContainerController controller =
                 createAppWindowController();
 
@@ -68,7 +69,7 @@
     }
 
     @Test
-    public void testSetOrientation() throws Exception {
+    public void testSetOrientation() {
         final WindowTestUtils.TestAppWindowContainerController controller =
                 createAppWindowController();
 
@@ -84,7 +85,7 @@
         assertEquals(SCREEN_ORIENTATION_UNSPECIFIED, controller.getOrientation());
 
         // Reset display frozen state
-        sWm.mDisplayFrozen = false;
+        mWm.mDisplayFrozen = false;
     }
 
     private void assertHasStartingWindow(AppWindowToken atoken) {
@@ -103,10 +104,10 @@
     }
 
     @Test
-    public void testCreateRemoveStartingWindow() throws Exception {
+    public void testCreateRemoveStartingWindow() {
         final WindowTestUtils.TestAppWindowContainerController controller =
                 createAppWindowController();
-        controller.addStartingWindow(InstrumentationRegistry.getContext().getPackageName(),
+        controller.addStartingWindow(mPackageName,
                 android.R.style.Theme, null, "Test", 0, 0, 0, 0, null, true, true, false, true,
                 false, false);
         waitUntilHandlersIdle();
@@ -118,34 +119,34 @@
     }
 
     @Test
-    public void testAddRemoveRace() throws Exception {
-
+    public void testAddRemoveRace() {
         // There was once a race condition between adding and removing starting windows
         for (int i = 0; i < 1000; i++) {
             final WindowTestUtils.TestAppWindowContainerController controller =
                     createAppWindowController();
-            controller.addStartingWindow(InstrumentationRegistry.getContext().getPackageName(),
+            controller.addStartingWindow(mPackageName,
                     android.R.style.Theme, null, "Test", 0, 0, 0, 0, null, true, true, false, true,
                     false, false);
             controller.removeStartingWindow();
             waitUntilHandlersIdle();
             assertNoStartingWindow(controller.getAppWindowToken(mDisplayContent));
 
-            controller.getAppWindowToken(mDisplayContent).getParent().getParent().removeImmediately();
+            controller.getAppWindowToken(
+                    mDisplayContent).getParent().getParent().removeImmediately();
         }
     }
 
     @Test
-    public void testTransferStartingWindow() throws Exception {
+    public void testTransferStartingWindow() {
         final WindowTestUtils.TestAppWindowContainerController controller1 =
                 createAppWindowController();
         final WindowTestUtils.TestAppWindowContainerController controller2 =
                 createAppWindowController();
-        controller1.addStartingWindow(InstrumentationRegistry.getContext().getPackageName(),
+        controller1.addStartingWindow(mPackageName,
                 android.R.style.Theme, null, "Test", 0, 0, 0, 0, null, true, true, false, true,
                 false, false);
         waitUntilHandlersIdle();
-        controller2.addStartingWindow(InstrumentationRegistry.getContext().getPackageName(),
+        controller2.addStartingWindow(mPackageName,
                 android.R.style.Theme, null, "Test", 0, 0, 0, 0, controller1.mToken.asBinder(),
                 true, true, false, true, false, false);
         waitUntilHandlersIdle();
@@ -154,19 +155,19 @@
     }
 
     @Test
-    public void testTransferStartingWindowWhileCreating() throws Exception {
+    public void testTransferStartingWindowWhileCreating() {
         final WindowTestUtils.TestAppWindowContainerController controller1 =
                 createAppWindowController();
         final WindowTestUtils.TestAppWindowContainerController controller2 =
                 createAppWindowController();
-        ((TestWindowManagerPolicy) sWm.mPolicy).setRunnableWhenAddingSplashScreen(() -> {
+        ((TestWindowManagerPolicy) mWm.mPolicy).setRunnableWhenAddingSplashScreen(() -> {
 
             // Surprise, ...! Transfer window in the middle of the creation flow.
-            controller2.addStartingWindow(InstrumentationRegistry.getContext().getPackageName(),
+            controller2.addStartingWindow(mPackageName,
                     android.R.style.Theme, null, "Test", 0, 0, 0, 0, controller1.mToken.asBinder(),
                     true, true, false, true, false, false);
         });
-        controller1.addStartingWindow(InstrumentationRegistry.getContext().getPackageName(),
+        controller1.addStartingWindow(mPackageName,
                 android.R.style.Theme, null, "Test", 0, 0, 0, 0, null, true, true, false, true,
                 false, false);
         waitUntilHandlersIdle();
@@ -175,7 +176,7 @@
     }
 
     @Test
-    public void testTryTransferStartingWindowFromHiddenAboveToken() throws Exception {
+    public void testTryTransferStartingWindowFromHiddenAboveToken() {
 
         // Add two tasks on top of each other.
         TestTaskWindowContainerController taskController =
@@ -186,7 +187,7 @@
                 createAppWindowController(taskController);
 
         // Add a starting window.
-        controllerTop.addStartingWindow(InstrumentationRegistry.getContext().getPackageName(),
+        controllerTop.addStartingWindow(mPackageName,
                 android.R.style.Theme, null, "Test", 0, 0, 0, 0, null, true, true, false, true,
                 false, false);
         waitUntilHandlersIdle();
@@ -202,7 +203,7 @@
     }
 
     @Test
-    public void testReparent() throws Exception {
+    public void testReparent() {
         final StackWindowController stackController =
             createStackControllerOnDisplay(mDisplayContent);
         final WindowTestUtils.TestTaskWindowContainerController taskController1 =
diff --git a/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenAnimationTests.java b/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenAnimationTests.java
index e3ab5cf..4522494 100644
--- a/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenAnimationTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenAnimationTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -26,15 +26,14 @@
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.verify;
 
-import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
-
 import android.view.SurfaceControl;
 
+import androidx.test.filters.SmallTest;
+
 import com.android.server.wm.WindowTestUtils.TestAppWindowToken;
 
+import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
@@ -43,10 +42,9 @@
  * Animation related tests for the {@link AppWindowToken} class.
  *
  * Build/Install/Run:
- * atest FrameworksServicesTests:com.android.server.wm.AppWindowTokenAnimationTests
+ *  atest FrameworksServicesTests:AppWindowTokenAnimationTests
  */
 @SmallTest
-@RunWith(AndroidJUnit4.class)
 public class AppWindowTokenAnimationTests extends WindowTestsBase {
 
     private TestAppWindowToken mToken;
@@ -56,9 +54,8 @@
     @Mock
     private AnimationAdapter mSpec;
 
-    @Override
+    @Before
     public void setUp() throws Exception {
-        super.setUp();
         MockitoAnnotations.initMocks(this);
 
         mToken = createTestAppWindowToken(mDisplayContent, WINDOWING_MODE_FULLSCREEN,
@@ -67,7 +64,7 @@
     }
 
     @Test
-    public void clipAfterAnim_boundsLayerIsCreated() throws Exception {
+    public void clipAfterAnim_boundsLayerIsCreated() {
         mToken.mNeedsAnimationBoundsLayer = true;
 
         mToken.mSurfaceAnimator.startAnimation(mTransaction, mSpec, true /* hidden */);
@@ -78,7 +75,7 @@
     }
 
     @Test
-    public void clipAfterAnim_boundsLayerIsDestroyed() throws Exception {
+    public void clipAfterAnim_boundsLayerIsDestroyed() {
         mToken.mNeedsAnimationBoundsLayer = true;
         mToken.mSurfaceAnimator.startAnimation(mTransaction, mSpec, true /* hidden */);
         final SurfaceControl leash = mToken.mSurfaceAnimator.mLeash;
@@ -95,7 +92,7 @@
     }
 
     @Test
-    public void clipAfterAnimCancelled_boundsLayerIsDestroyed() throws Exception {
+    public void clipAfterAnimCancelled_boundsLayerIsDestroyed() {
         mToken.mNeedsAnimationBoundsLayer = true;
         mToken.mSurfaceAnimator.startAnimation(mTransaction, mSpec, true /* hidden */);
         final SurfaceControl leash = mToken.mSurfaceAnimator.mLeash;
@@ -108,7 +105,7 @@
     }
 
     @Test
-    public void clipNoneAnim_boundsLayerIsNotCreated() throws Exception {
+    public void clipNoneAnim_boundsLayerIsNotCreated() {
         mToken.mNeedsAnimationBoundsLayer = false;
 
         mToken.mSurfaceAnimator.startAnimation(mTransaction, mSpec, true /* hidden */);
diff --git a/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenTests.java b/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenTests.java
index 7935ec1..a8e1ed4 100644
--- a/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/AppWindowTokenTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -47,31 +47,27 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
+import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Tests for the {@link AppWindowToken} class.
  *
  * Build/Install/Run:
- *  atest FrameworksServicesTests:com.android.server.wm.AppWindowTokenTests
+ *  atest FrameworksServicesTests:AppWindowTokenTests
  */
+@FlakyTest(bugId = 68267650)
 @SmallTest
-// TODO: b/68267650
-// @Presubmit
-@RunWith(AndroidJUnit4.class)
+@Presubmit
 public class AppWindowTokenTests extends WindowTestsBase {
 
     TaskStack mStack;
     Task mTask;
     WindowTestUtils.TestAppWindowToken mToken;
 
-    @Override
+    @Before
     public void setUp() throws Exception {
-        super.setUp();
-
         mStack = createTaskStackOnDisplay(mDisplayContent);
         mTask = createTaskInStack(mStack, 0 /* userId */);
         mToken = WindowTestUtils.createTestAppWindowToken(mDisplayContent);
@@ -81,7 +77,7 @@
 
     @Test
     @Presubmit
-    public void testAddWindow_Order() throws Exception {
+    public void testAddWindow_Order() {
         assertEquals(0, mToken.getWindowsCount());
 
         final WindowState win1 = createWindow(null, TYPE_APPLICATION, mToken, "win1");
@@ -107,7 +103,7 @@
 
     @Test
     @Presubmit
-    public void testFindMainWindow() throws Exception {
+    public void testFindMainWindow() {
         assertNull(mToken.findMainWindow());
 
         final WindowState window1 = createWindow(null, TYPE_BASE_APPLICATION, mToken, "window1");
@@ -123,7 +119,7 @@
 
     @Test
     @Presubmit
-    public void testGetTopFullscreenWindow() throws Exception {
+    public void testGetTopFullscreenWindow() {
         assertNull(mToken.getTopFullscreenWindow());
 
         final WindowState window1 = createWindow(null, TYPE_BASE_APPLICATION, mToken, "window1");
@@ -138,10 +134,10 @@
     }
 
     @Test
-    public void testLandscapeSeascapeRotationByApp() throws Exception {
+    public void testLandscapeSeascapeRotationByApp() {
         // Some plumbing to get the service ready for rotation updates.
-        sWm.mDisplayReady = true;
-        sWm.mDisplayEnabled = true;
+        mWm.mDisplayReady = true;
+        mWm.mDisplayEnabled = true;
 
         final WindowManager.LayoutParams attrs = new WindowManager.LayoutParams(
                 TYPE_BASE_APPLICATION);
@@ -151,26 +147,26 @@
 
         // Set initial orientation and update.
         mToken.setOrientation(SCREEN_ORIENTATION_LANDSCAPE);
-        sWm.updateOrientationFromAppTokens(mDisplayContent.getOverrideConfiguration(), null,
+        mWm.updateOrientationFromAppTokens(mDisplayContent.getOverrideConfiguration(), null,
                 mDisplayContent.getDisplayId());
         assertEquals(SCREEN_ORIENTATION_LANDSCAPE, mDisplayContent.getLastOrientation());
         appWindow.resizeReported = false;
 
         // Update the orientation to perform 180 degree rotation and check that resize was reported.
         mToken.setOrientation(SCREEN_ORIENTATION_REVERSE_LANDSCAPE);
-        sWm.updateOrientationFromAppTokens(mDisplayContent.getOverrideConfiguration(), null,
+        mWm.updateOrientationFromAppTokens(mDisplayContent.getOverrideConfiguration(), null,
                 mDisplayContent.getDisplayId());
-        sWm.mRoot.performSurfacePlacement(false /* recoveringMemory */);
+        mWm.mRoot.performSurfacePlacement(false /* recoveringMemory */);
         assertEquals(SCREEN_ORIENTATION_REVERSE_LANDSCAPE, mDisplayContent.getLastOrientation());
         assertTrue(appWindow.resizeReported);
         appWindow.removeImmediately();
     }
 
     @Test
-    public void testLandscapeSeascapeRotationByPolicy() throws Exception {
+    public void testLandscapeSeascapeRotationByPolicy() {
         // Some plumbing to get the service ready for rotation updates.
-        sWm.mDisplayReady = true;
-        sWm.mDisplayEnabled = true;
+        mWm.mDisplayReady = true;
+        mWm.mDisplayEnabled = true;
 
         final DisplayRotation spiedRotation = spy(mDisplayContent.getDisplayRotation());
         mDisplayContent.setDisplayRotation(spiedRotation);
@@ -194,15 +190,15 @@
 
     private void performRotation(DisplayRotation spiedRotation, int rotationToReport) {
         doReturn(rotationToReport).when(spiedRotation).rotationForOrientation(anyInt(), anyInt());
-        sWm.updateRotation(false, false);
+        mWm.updateRotation(false, false);
         // Prevent the next rotation from being deferred by animation.
-        sWm.mAnimator.setScreenRotationAnimationLocked(mDisplayContent.getDisplayId(), null);
-        sWm.mRoot.performSurfacePlacement(false /* recoveringMemory */);
+        mWm.mAnimator.setScreenRotationAnimationLocked(mDisplayContent.getDisplayId(), null);
+        mWm.mRoot.performSurfacePlacement(false /* recoveringMemory */);
     }
 
     @Test
     @Presubmit
-    public void testGetOrientation() throws Exception {
+    public void testGetOrientation() {
         mToken.setOrientation(SCREEN_ORIENTATION_LANDSCAPE);
 
         mToken.setFillsParent(false);
@@ -220,7 +216,7 @@
 
     @Test
     @Presubmit
-    public void testKeyguardFlagsDuringRelaunch() throws Exception {
+    public void testKeyguardFlagsDuringRelaunch() {
         final WindowManager.LayoutParams attrs = new WindowManager.LayoutParams(
                 TYPE_BASE_APPLICATION);
         attrs.flags |= FLAG_SHOW_WHEN_LOCKED | FLAG_DISMISS_KEYGUARD;
@@ -246,7 +242,7 @@
 
     @Test
     @FlakyTest(detail = "Promote once confirmed non-flaky")
-    public void testStuckExitingWindow() throws Exception {
+    public void testStuckExitingWindow() {
         final WindowState closingWindow = createWindow(null, FIRST_APPLICATION_WINDOW,
                 "closingWindow");
         closingWindow.mAnimatingExit = true;
diff --git a/services/tests/servicestests/src/com/android/server/wm/BoundsAnimationControllerTests.java b/services/tests/servicestests/src/com/android/server/wm/BoundsAnimationControllerTests.java
index d65055c..1c5391e 100644
--- a/services/tests/servicestests/src/com/android/server/wm/BoundsAnimationControllerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/BoundsAnimationControllerTests.java
@@ -11,12 +11,12 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
 
-import static android.view.Display.DEFAULT_DISPLAY;
+import static androidx.test.platform.app.InstrumentationRegistry.getInstrumentation;
 
 import static com.android.server.wm.BoundsAnimationController.NO_PIP_MODE_CHANGED_CALLBACKS;
 import static com.android.server.wm.BoundsAnimationController.SCHEDULE_PIP_MODE_CHANGED_ON_END;
@@ -24,11 +24,11 @@
 import static com.android.server.wm.BoundsAnimationController.SchedulePipModeChangedState;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
 
 import android.animation.ValueAnimator;
 import android.content.Context;
@@ -37,16 +37,14 @@
 import android.os.Looper;
 import android.platform.test.annotations.Presubmit;
 
-import androidx.test.InstrumentationRegistry;
 import androidx.test.annotation.UiThreadTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.wm.BoundsAnimationController.BoundsAnimator;
 import com.android.server.wm.WindowManagerInternal.AppTransitionListener;
 
+import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Test class for {@link BoundsAnimationController} to ensure that it sends the right callbacks
@@ -59,21 +57,20 @@
  * appropriately.
  *
  * Build/Install/Run:
- *  bit FrameworksServicesTests:com.android.server.wm.BoundsAnimationControllerTests
+ *  atest FrameworksServicesTests:BoundsAnimationControllerTests
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class BoundsAnimationControllerTests extends WindowTestsBase {
 
     /**
      * Mock value animator to simulate updates with.
      */
-    private class MockValueAnimator extends ValueAnimator {
+    private static class MockValueAnimator extends ValueAnimator {
 
         private float mFraction;
 
-        public MockValueAnimator getWithValue(float fraction) {
+        MockValueAnimator getWithValue(float fraction) {
             mFraction = fraction;
             return this;
         }
@@ -87,12 +84,12 @@
     /**
      * Mock app transition to fire notifications to the bounds animator.
      */
-    private class MockAppTransition extends AppTransition {
+    private static class MockAppTransition extends AppTransition {
 
         private AppTransitionListener mListener;
 
-        MockAppTransition(Context context) {
-            super(context, sWm, mDisplayContent);
+        MockAppTransition(Context context, WindowManagerService wm, DisplayContent displayContent) {
+            super(context, wm, displayContent);
         }
 
         @Override
@@ -120,7 +117,7 @@
     /**
      * A test animate bounds user to track callbacks from the bounds animation.
      */
-    private class TestBoundsAnimationTarget implements BoundsAnimationTarget {
+    private static class TestBoundsAnimationTarget implements BoundsAnimationTarget {
 
         boolean mAwaitingAnimationStart;
         boolean mMovedToFullscreen;
@@ -193,21 +190,23 @@
     /**
      * Drives the animations, makes common assertions along the way.
      */
-    private class BoundsAnimationDriver {
+    private static class BoundsAnimationDriver {
 
-        private BoundsAnimationController mController;
-        private TestBoundsAnimationTarget mTarget;
+        private final BoundsAnimationController mController;
+        private final TestBoundsAnimationTarget mTarget;
+        private final MockValueAnimator mMockAnimator;
+
         private BoundsAnimator mAnimator;
-
         private Rect mFrom;
         private Rect mTo;
         private Rect mLargerBounds;
         private Rect mExpectedFinalBounds;
 
         BoundsAnimationDriver(BoundsAnimationController controller,
-                TestBoundsAnimationTarget target) {
+                TestBoundsAnimationTarget target, MockValueAnimator mockValueAnimator) {
             mController = controller;
             mTarget = target;
+            mMockAnimator = mockValueAnimator;
         }
 
         BoundsAnimationDriver start(Rect from, Rect to) {
@@ -222,7 +221,7 @@
 
             // Started, not running
             assertTrue(mTarget.mAwaitingAnimationStart);
-            assertTrue(!mTarget.mAnimationStarted);
+            assertFalse(mTarget.mAnimationStarted);
 
             startImpl(from, to);
 
@@ -236,7 +235,7 @@
             }
 
             // Started and running
-            assertTrue(!mTarget.mAwaitingAnimationStart);
+            assertFalse(mTarget.mAwaitingAnimationStart);
             assertTrue(mTarget.mAnimationStarted);
 
             return this;
@@ -268,7 +267,7 @@
                 assertTrue(mTarget.mForcePipModeChangedCallback);
             } else {
                 // No animation start for replacing animation
-                assertTrue(!mTarget.mAnimationStarted);
+                assertFalse(mTarget.mAnimationStarted);
             }
             mTarget.mAnimationStarted = true;
             return this;
@@ -297,7 +296,7 @@
 
             // Animating to larger size
             if (mFrom.equals(mLargerBounds)) {
-                assertTrue(!mAnimator.animatingToLargerSize());
+                assertFalse(mAnimator.animatingToLargerSize());
             } else if (mTo.equals(mLargerBounds)) {
                 assertTrue(mAnimator.animatingToLargerSize());
             }
@@ -339,10 +338,10 @@
             mAnimator.onAnimationUpdate(mMockAnimator.getWithValue(0.5f));
 
             // Not started, not running, cancel reset
-            assertTrue(!mTarget.mCancelRequested);
+            assertFalse(mTarget.mCancelRequested);
 
             // Stack/task bounds not updated
-            assertTrue(!mTarget.mBoundsUpdated);
+            assertFalse(mTarget.mBoundsUpdated);
 
             // Callback made
             assertTrue(mTarget.mAnimationEnded);
@@ -372,14 +371,10 @@
             return this;
         }
 
-        private Rect getLargerBounds(Rect r1, Rect r2) {
+        private static Rect getLargerBounds(Rect r1, Rect r2) {
             int r1Area = r1.width() * r1.height();
             int r2Area = r2.width() * r2.height();
-            if (r1Area <= r2Area) {
-                return r2;
-            } else {
-                return r1;
-            }
+            return (r1Area <= r2Area) ? r2 : r1;
         }
     }
 
@@ -395,32 +390,29 @@
 
     // Common
     private MockAppTransition mMockAppTransition;
-    private MockValueAnimator mMockAnimator;
     private TestBoundsAnimationTarget mTarget;
     private BoundsAnimationController mController;
     private BoundsAnimationDriver mDriver;
 
     // Temp
-    private Rect mTmpRect = new Rect();
+    private static final Rect sTmpRect = new Rect();
 
-    @Override
+    @Before
     public void setUp() throws Exception {
-        super.setUp();
-
-        final Context context = InstrumentationRegistry.getTargetContext();
+        final Context context = getInstrumentation().getTargetContext();
         final Handler handler = new Handler(Looper.getMainLooper());
-        mMockAppTransition = new MockAppTransition(context);
-        mMockAnimator = new MockValueAnimator();
+        mMockAppTransition = new MockAppTransition(context, mWm, mDisplayContent);
         mTarget = new TestBoundsAnimationTarget();
         mController = new BoundsAnimationController(context, mMockAppTransition, handler, null);
-        mDriver = new BoundsAnimationDriver(mController, mTarget);
+        final MockValueAnimator mockValueAnimator = new MockValueAnimator();
+        mDriver = new BoundsAnimationDriver(mController, mTarget, mockValueAnimator);
     }
 
     /** BASE TRANSITIONS **/
 
     @UiThreadTest
     @Test
-    public void testFullscreenToFloatingTransition() throws Exception {
+    public void testFullscreenToFloatingTransition() {
         mDriver.start(BOUNDS_FULL, BOUNDS_FLOATING)
                 .expectStarted(!SCHEDULE_PIP_MODE_CHANGED)
                 .update(0f)
@@ -432,7 +424,7 @@
 
     @UiThreadTest
     @Test
-    public void testFloatingToFullscreenTransition() throws Exception {
+    public void testFloatingToFullscreenTransition() {
         mDriver.start(BOUNDS_FLOATING, BOUNDS_FULL)
                 .expectStarted(SCHEDULE_PIP_MODE_CHANGED)
                 .update(0f)
@@ -444,7 +436,7 @@
 
     @UiThreadTest
     @Test
-    public void testFloatingToSmallerFloatingTransition() throws Exception {
+    public void testFloatingToSmallerFloatingTransition() {
         mDriver.start(BOUNDS_FLOATING, BOUNDS_SMALLER_FLOATING)
                 .expectStarted(!SCHEDULE_PIP_MODE_CHANGED)
                 .update(0f)
@@ -456,7 +448,7 @@
 
     @UiThreadTest
     @Test
-    public void testFloatingToLargerFloatingTransition() throws Exception {
+    public void testFloatingToLargerFloatingTransition() {
         mDriver.start(BOUNDS_SMALLER_FLOATING, BOUNDS_FLOATING)
                 .expectStarted(!SCHEDULE_PIP_MODE_CHANGED)
                 .update(0f)
@@ -470,7 +462,7 @@
 
     @UiThreadTest
     @Test
-    public void testFullscreenToFloatingCancelFromTarget() throws Exception {
+    public void testFullscreenToFloatingCancelFromTarget() {
         mDriver.start(BOUNDS_FULL, BOUNDS_FLOATING)
                 .expectStarted(!SCHEDULE_PIP_MODE_CHANGED)
                 .update(0.25f)
@@ -480,7 +472,7 @@
 
     @UiThreadTest
     @Test
-    public void testFullscreenToFloatingCancelFromAnimationToSameBounds() throws Exception {
+    public void testFullscreenToFloatingCancelFromAnimationToSameBounds() {
         mDriver.start(BOUNDS_FULL, BOUNDS_FLOATING)
                 .expectStarted(!SCHEDULE_PIP_MODE_CHANGED)
                 .update(0.25f)
@@ -491,7 +483,7 @@
 
     @UiThreadTest
     @Test
-    public void testFullscreenToFloatingCancelFromAnimationToFloatingBounds() throws Exception {
+    public void testFullscreenToFloatingCancelFromAnimationToFloatingBounds() {
         mDriver.start(BOUNDS_FULL, BOUNDS_FLOATING)
                 .expectStarted(!SCHEDULE_PIP_MODE_CHANGED)
                 .update(0.25f)
@@ -503,7 +495,7 @@
 
     @UiThreadTest
     @Test
-    public void testFullscreenToFloatingCancelFromAnimationToFullscreenBounds() throws Exception {
+    public void testFullscreenToFloatingCancelFromAnimationToFullscreenBounds() {
         // When animating from fullscreen and the animation is interruped, we expect the animation
         // start callback to be made, with a forced pip mode change callback
         mDriver.start(BOUNDS_FULL, BOUNDS_FLOATING)
@@ -518,7 +510,7 @@
 
     @UiThreadTest
     @Test
-    public void testFloatingToFullscreenCancelFromTarget() throws Exception {
+    public void testFloatingToFullscreenCancelFromTarget() {
         mDriver.start(BOUNDS_FLOATING, BOUNDS_FULL)
                 .expectStarted(SCHEDULE_PIP_MODE_CHANGED)
                 .update(0.25f)
@@ -528,7 +520,7 @@
 
     @UiThreadTest
     @Test
-    public void testFloatingToFullscreenCancelFromAnimationToSameBounds() throws Exception {
+    public void testFloatingToFullscreenCancelFromAnimationToSameBounds() {
         mDriver.start(BOUNDS_FLOATING, BOUNDS_FULL)
                 .expectStarted(SCHEDULE_PIP_MODE_CHANGED)
                 .update(0.25f)
@@ -539,7 +531,7 @@
 
     @UiThreadTest
     @Test
-    public void testFloatingToFullscreenCancelFromAnimationToFloatingBounds() throws Exception {
+    public void testFloatingToFullscreenCancelFromAnimationToFloatingBounds() {
         mDriver.start(BOUNDS_FLOATING, BOUNDS_FULL)
                 .expectStarted(SCHEDULE_PIP_MODE_CHANGED)
                 .update(0.25f)
@@ -553,7 +545,7 @@
 
     @UiThreadTest
     @Test
-    public void testFloatingToSmallerFloatingCancelFromTarget() throws Exception {
+    public void testFloatingToSmallerFloatingCancelFromTarget() {
         mDriver.start(BOUNDS_FLOATING, BOUNDS_SMALLER_FLOATING)
                 .expectStarted(!SCHEDULE_PIP_MODE_CHANGED)
                 .update(0.25f)
@@ -563,7 +555,7 @@
 
     @UiThreadTest
     @Test
-    public void testFloatingToLargerFloatingCancelFromTarget() throws Exception {
+    public void testFloatingToLargerFloatingCancelFromTarget() {
         mDriver.start(BOUNDS_SMALLER_FLOATING, BOUNDS_FLOATING)
                 .expectStarted(!SCHEDULE_PIP_MODE_CHANGED)
                 .update(0.25f)
@@ -575,7 +567,7 @@
 
     @UiThreadTest
     @Test
-    public void testBoundsAreCopied() throws Exception {
+    public void testBoundsAreCopied() {
         Rect from = new Rect(0, 0, 100, 100);
         Rect to = new Rect(25, 25, 75, 75);
         mDriver.start(from, to)
@@ -588,9 +580,9 @@
     /**
      * @return whether the task and stack bounds would be the same if they were at the same offset.
      */
-    private boolean assertEqualSizeAtOffset(Rect stackBounds, Rect taskBounds) {
-        mTmpRect.set(taskBounds);
-        mTmpRect.offsetTo(stackBounds.left, stackBounds.top);
-        return stackBounds.equals(mTmpRect);
+    private static boolean assertEqualSizeAtOffset(Rect stackBounds, Rect taskBounds) {
+        sTmpRect.set(taskBounds);
+        sTmpRect.offsetTo(stackBounds.left, stackBounds.top);
+        return stackBounds.equals(sTmpRect);
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/DimmerTests.java b/services/tests/servicestests/src/com/android/server/wm/DimmerTests.java
index 21555e3..b6a7cfb 100644
--- a/services/tests/servicestests/src/com/android/server/wm/DimmerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/DimmerTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -32,26 +32,22 @@
 import android.view.SurfaceControl;
 import android.view.SurfaceSession;
 
-import androidx.test.runner.AndroidJUnit4;
-
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Build/Install/Run:
- * atest FrameworksServicesTests:com.android.server.wm.DimmerTests;
+ *  atest FrameworksServicesTests:DimmerTests;
  */
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class DimmerTests extends WindowTestsBase {
 
-    private class TestWindowContainer extends WindowContainer<TestWindowContainer> {
+    private static class TestWindowContainer extends WindowContainer<TestWindowContainer> {
         final SurfaceControl mControl = mock(SurfaceControl.class);
         final SurfaceControl.Transaction mTransaction = mock(SurfaceControl.Transaction.class);
 
-        TestWindowContainer() {
-            super(sWm);
+        TestWindowContainer(WindowManagerService wm) {
+            super(wm);
         }
 
         @Override
@@ -65,13 +61,13 @@
         }
     }
 
-    private class MockSurfaceBuildingContainer extends WindowContainer<TestWindowContainer> {
+    private static class MockSurfaceBuildingContainer extends WindowContainer<TestWindowContainer> {
         final SurfaceSession mSession = new SurfaceSession();
         final SurfaceControl mHostControl = mock(SurfaceControl.class);
         final SurfaceControl.Transaction mHostTransaction = mock(SurfaceControl.Transaction.class);
 
-        MockSurfaceBuildingContainer() {
-            super(sWm);
+        MockSurfaceBuildingContainer(WindowManagerService wm) {
+            super(wm);
         }
 
         class MockSurfaceBuilder extends SurfaceControl.Builder {
@@ -116,15 +112,14 @@
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
-        mHost = new MockSurfaceBuildingContainer();
+        mHost = new MockSurfaceBuildingContainer(mWm);
         mSurfaceAnimatorStarter = spy(new SurfaceAnimatorStarterImpl());
         mTransaction = mock(SurfaceControl.Transaction.class);
         mDimmer = new Dimmer(mHost, mSurfaceAnimatorStarter);
     }
 
     @Test
-    public void testDimAboveNoChildCreatesSurface() throws Exception {
+    public void testDimAboveNoChildCreatesSurface() {
         final float alpha = 0.8f;
         mDimmer.dimAbove(mTransaction, alpha);
 
@@ -137,7 +132,7 @@
     }
 
     @Test
-    public void testDimAboveNoChildRedundantlyUpdatesAlphaOnExistingSurface() throws Exception {
+    public void testDimAboveNoChildRedundantlyUpdatesAlphaOnExistingSurface() {
         float alpha = 0.8f;
         mDimmer.dimAbove(mTransaction, alpha);
         final SurfaceControl firstSurface = getDimLayer();
@@ -150,7 +145,7 @@
     }
 
     @Test
-    public void testUpdateDimsAppliesSize() throws Exception {
+    public void testUpdateDimsAppliesSize() {
         mDimmer.dimAbove(mTransaction, 0.8f);
 
         int width = 100;
@@ -163,7 +158,7 @@
     }
 
     @Test
-    public void testDimAboveNoChildNotReset() throws Exception {
+    public void testDimAboveNoChildNotReset() {
         mDimmer.dimAbove(mTransaction, 0.8f);
         SurfaceControl dimLayer = getDimLayer();
         mDimmer.resetDimStates();
@@ -174,8 +169,8 @@
     }
 
     @Test
-    public void testDimAboveWithChildCreatesSurfaceAboveChild() throws Exception {
-        TestWindowContainer child = new TestWindowContainer();
+    public void testDimAboveWithChildCreatesSurfaceAboveChild() {
+        TestWindowContainer child = new TestWindowContainer(mWm);
         mHost.addChild(child, 0);
 
         final float alpha = 0.8f;
@@ -189,8 +184,8 @@
     }
 
     @Test
-    public void testDimBelowWithChildSurfaceCreatesSurfaceBelowChild() throws Exception {
-        TestWindowContainer child = new TestWindowContainer();
+    public void testDimBelowWithChildSurfaceCreatesSurfaceBelowChild() {
+        TestWindowContainer child = new TestWindowContainer(mWm);
         mHost.addChild(child, 0);
 
         final float alpha = 0.8f;
@@ -204,8 +199,8 @@
     }
 
     @Test
-    public void testDimBelowWithChildSurfaceDestroyedWhenReset() throws Exception {
-        TestWindowContainer child = new TestWindowContainer();
+    public void testDimBelowWithChildSurfaceDestroyedWhenReset() {
+        TestWindowContainer child = new TestWindowContainer(mWm);
         mHost.addChild(child, 0);
 
         final float alpha = 0.8f;
@@ -220,8 +215,8 @@
     }
 
     @Test
-    public void testDimBelowWithChildSurfaceNotDestroyedWhenPersisted() throws Exception {
-        TestWindowContainer child = new TestWindowContainer();
+    public void testDimBelowWithChildSurfaceNotDestroyedWhenPersisted() {
+        TestWindowContainer child = new TestWindowContainer(mWm);
         mHost.addChild(child, 0);
 
         final float alpha = 0.8f;
@@ -236,9 +231,9 @@
     }
 
     @Test
-    public void testDimUpdateWhileDimming() throws Exception {
+    public void testDimUpdateWhileDimming() {
         Rect bounds = new Rect();
-        TestWindowContainer child = new TestWindowContainer();
+        TestWindowContainer child = new TestWindowContainer(mWm);
         mHost.addChild(child, 0);
 
         final float alpha = 0.8f;
@@ -258,8 +253,8 @@
     }
 
     @Test
-    public void testRemoveDimImmediately() throws Exception {
-        TestWindowContainer child = new TestWindowContainer();
+    public void testRemoveDimImmediately() {
+        TestWindowContainer child = new TestWindowContainer(mWm);
         mHost.addChild(child, 0);
 
         mDimmer.dimAbove(mTransaction, child, 1);
diff --git a/services/tests/servicestests/src/com/android/server/wm/DisplayContentTests.java b/services/tests/servicestests/src/com/android/server/wm/DisplayContentTests.java
index 8b75570..dd374e9 100644
--- a/services/tests/servicestests/src/com/android/server/wm/DisplayContentTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/DisplayContentTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -53,7 +53,6 @@
 import android.os.SystemClock;
 import android.platform.test.annotations.Presubmit;
 import android.util.DisplayMetrics;
-import android.util.SparseIntArray;
 import android.view.DisplayCutout;
 import android.view.Gravity;
 import android.view.MotionEvent;
@@ -61,12 +60,10 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.wm.utils.WmDisplayCutout;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -78,16 +75,15 @@
  * Tests for the {@link DisplayContent} class.
  *
  * Build/Install/Run:
- *  atest com.android.server.wm.DisplayContentTests
+ *  atest FrameworksServicesTests:DisplayContentTests
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class DisplayContentTests extends WindowTestsBase {
 
     @Test
     @FlakyTest(bugId = 77772044)
-    public void testForAllWindows() throws Exception {
+    public void testForAllWindows() {
         final WindowState exitingAppWindow = createWindow(null, TYPE_BASE_APPLICATION,
                 mDisplayContent, "exiting app");
         final AppWindowToken exitingAppToken = exitingAppWindow.mAppToken;
@@ -108,11 +104,11 @@
     }
 
     @Test
-    public void testForAllWindows_WithAppImeTarget() throws Exception {
+    public void testForAllWindows_WithAppImeTarget() {
         final WindowState imeAppTarget =
                 createWindow(null, TYPE_BASE_APPLICATION, mDisplayContent, "imeAppTarget");
 
-        sWm.mInputMethodTarget = imeAppTarget;
+        mWm.mInputMethodTarget = imeAppTarget;
 
         assertForAllWindowsOrder(Arrays.asList(
                 mWallpaperWindow,
@@ -128,8 +124,8 @@
     }
 
     @Test
-    public void testForAllWindows_WithChildWindowImeTarget() throws Exception {
-        sWm.mInputMethodTarget = mChildAppWindowAbove;
+    public void testForAllWindows_WithChildWindowImeTarget() {
+        mWm.mInputMethodTarget = mChildAppWindowAbove;
 
         assertForAllWindowsOrder(Arrays.asList(
                 mWallpaperWindow,
@@ -144,8 +140,8 @@
     }
 
     @Test
-    public void testForAllWindows_WithStatusBarImeTarget() throws Exception {
-        sWm.mInputMethodTarget = mStatusBarWindow;
+    public void testForAllWindows_WithStatusBarImeTarget() {
+        mWm.mInputMethodTarget = mStatusBarWindow;
 
         assertForAllWindowsOrder(Arrays.asList(
                 mWallpaperWindow,
@@ -160,7 +156,7 @@
     }
 
     @Test
-    public void testForAllWindows_WithInBetweenWindowToken() throws Exception {
+    public void testForAllWindows_WithInBetweenWindowToken() {
         // This window is set-up to be z-ordered between some windows that go in the same token like
         // the nav bar and status bar.
         final WindowState voiceInteractionWindow = createWindow(null, TYPE_VOICE_INTERACTION,
@@ -180,7 +176,7 @@
     }
 
     @Test
-    public void testComputeImeTarget() throws Exception {
+    public void testComputeImeTarget() {
         // Verify that an app window can be an ime target.
         final WindowState appWin = createWindow(null, TYPE_APPLICATION, mDisplayContent, "appWin");
         appWin.setHasSurface(true);
@@ -203,7 +199,7 @@
      * container references updates.
      */
     @Test
-    public void testMoveStackBetweenDisplays() throws Exception {
+    public void testMoveStackBetweenDisplays() {
         // Create a second display.
         final DisplayContent dc = createNewDisplay();
 
@@ -233,7 +229,7 @@
      * This tests override configuration updates for display content.
      */
     @Test
-    public void testDisplayOverrideConfigUpdate() throws Exception {
+    public void testDisplayOverrideConfigUpdate() {
         final int displayId = mDisplayContent.getDisplayId();
         final Configuration currentOverrideConfig = mDisplayContent.getOverrideConfiguration();
 
@@ -242,7 +238,7 @@
         newOverrideConfig.densityDpi += 120;
         newOverrideConfig.fontScale += 0.3;
 
-        sWm.setNewDisplayOverrideConfiguration(newOverrideConfig, displayId);
+        mWm.setNewDisplayOverrideConfiguration(newOverrideConfig, displayId);
 
         // Check that override config is applied.
         assertEquals(newOverrideConfig, mDisplayContent.getOverrideConfiguration());
@@ -252,7 +248,7 @@
      * This tests global configuration updates when default display config is updated.
      */
     @Test
-    public void testDefaultDisplayOverrideConfigUpdate() throws Exception {
+    public void testDefaultDisplayOverrideConfigUpdate() {
         final Configuration currentConfig = mDisplayContent.getConfiguration();
 
         // Create new, slightly changed override configuration and apply it to the display.
@@ -260,16 +256,16 @@
         newOverrideConfig.densityDpi += 120;
         newOverrideConfig.fontScale += 0.3;
 
-        sWm.setNewDisplayOverrideConfiguration(newOverrideConfig, DEFAULT_DISPLAY);
+        mWm.setNewDisplayOverrideConfiguration(newOverrideConfig, DEFAULT_DISPLAY);
 
         // Check that global configuration is updated, as we've updated default display's config.
-        Configuration globalConfig = sWm.mRoot.getConfiguration();
+        Configuration globalConfig = mWm.mRoot.getConfiguration();
         assertEquals(newOverrideConfig.densityDpi, globalConfig.densityDpi);
         assertEquals(newOverrideConfig.fontScale, globalConfig.fontScale, 0.1 /* delta */);
 
         // Return back to original values.
-        sWm.setNewDisplayOverrideConfiguration(currentConfig, DEFAULT_DISPLAY);
-        globalConfig = sWm.mRoot.getConfiguration();
+        mWm.setNewDisplayOverrideConfiguration(currentConfig, DEFAULT_DISPLAY);
+        globalConfig = mWm.mRoot.getConfiguration();
         assertEquals(currentConfig.densityDpi, globalConfig.densityDpi);
         assertEquals(currentConfig.fontScale, globalConfig.fontScale, 0.1 /* delta */);
     }
@@ -278,8 +274,8 @@
      * Tests tapping on a stack in different display results in window gaining focus.
      */
     @Test
-    public void testInputEventBringsCorrectDisplayInFocus() throws Exception {
-        DisplayContent dc0 = sWm.getDefaultDisplayContentLocked();
+    public void testInputEventBringsCorrectDisplayInFocus() {
+        DisplayContent dc0 = mWm.getDefaultDisplayContentLocked();
         // Create a second display
         final DisplayContent dc1 = createNewDisplay();
 
@@ -303,51 +299,51 @@
         // tap on primary display.
         tapOnDisplay(dc0);
         // Check focus is on primary display.
-        assertEquals(sWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus,
+        assertEquals(mWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus,
                 dc0.findFocusedWindow());
 
         // Tap on secondary display.
         tapOnDisplay(dc1);
         // Check focus is on secondary.
-        assertEquals(sWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus,
+        assertEquals(mWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus,
                 dc1.findFocusedWindow());
     }
 
     @Test
-    public void testFocusedWindowMultipleDisplays() throws Exception {
+    public void testFocusedWindowMultipleDisplays() {
         // Create a focusable window and check that focus is calculated correctly
         final WindowState window1 =
                 createWindow(null, TYPE_BASE_APPLICATION, mDisplayContent, "window1");
         updateFocusedWindow();
         assertTrue(window1.isFocused());
-        assertEquals(window1, sWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus);
+        assertEquals(window1, mWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus);
 
         // Check that a new display doesn't affect focus
         final DisplayContent dc = createNewDisplay();
         updateFocusedWindow();
         assertTrue(window1.isFocused());
-        assertEquals(window1, sWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus);
+        assertEquals(window1, mWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus);
 
         // Add a window to the second display, and it should be focused
         final WindowState window2 = createWindow(null, TYPE_BASE_APPLICATION, dc, "window2");
         updateFocusedWindow();
         assertTrue(window1.isFocused());
         assertTrue(window2.isFocused());
-        assertEquals(window2, sWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus);
+        assertEquals(window2, mWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus);
 
         // Move the first window to the to including parents, and make sure focus is updated
         window1.getParent().positionChildAt(POSITION_TOP, window1, true);
         updateFocusedWindow();
         assertTrue(window1.isFocused());
         assertTrue(window2.isFocused());
-        assertEquals(window1, sWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus);
+        assertEquals(window1, mWm.mRoot.getTopFocusedDisplayContent().mCurrentFocus);
     }
 
     /**
      * This tests setting the maximum ui width on a display.
      */
     @Test
-    public void testMaxUiWidth() throws Exception {
+    public void testMaxUiWidth() {
         // Prevent base display metrics for test from being updated to the value of real display.
         final DisplayContent displayContent = createDisplayNoUpdateDisplayInfo();
         final int baseWidth = 1440;
@@ -439,8 +435,8 @@
     }
 
     @Test
-    public void testDisplayCutout_rot0() throws Exception {
-        synchronized (sWm.getWindowManagerLock()) {
+    public void testDisplayCutout_rot0() {
+        synchronized (mWm.getWindowManagerLock()) {
             final DisplayContent dc = createNewDisplay();
             dc.mInitialDisplayWidth = 200;
             dc.mInitialDisplayHeight = 400;
@@ -458,8 +454,8 @@
     }
 
     @Test
-    public void testDisplayCutout_rot90() throws Exception {
-        synchronized (sWm.getWindowManagerLock()) {
+    public void testDisplayCutout_rot90() {
+        synchronized (mWm.getWindowManagerLock()) {
             // Prevent mInitialDisplayCutout from being updated from real display (e.g. null
             // if the device has no cutout).
             final DisplayContent dc = createDisplayNoUpdateDisplayInfo();
@@ -476,7 +472,8 @@
 
             final Rect r1 = new Rect(left, top, right, bottom);
             final DisplayCutout cutout = new WmDisplayCutout(
-                    fromBoundingRect(r1.left, r1.top, r1.right, r1.bottom, BOUNDS_POSITION_TOP), null)
+                    fromBoundingRect(r1.left, r1.top, r1.right, r1.bottom, BOUNDS_POSITION_TOP),
+                    null)
                     .computeSafeInsets(displayWidth, displayHeight).getDisplayCutout();
 
             dc.mInitialDisplayCutout = cutout;
@@ -500,8 +497,8 @@
     }
 
     @Test
-    public void testLayoutSeq_assignedDuringLayout() throws Exception {
-        synchronized (sWm.getWindowManagerLock()) {
+    public void testLayoutSeq_assignedDuringLayout() {
+        synchronized (mWm.getWindowManagerLock()) {
 
             final DisplayContent dc = createNewDisplay();
             final WindowState win = createWindow(null /* parent */, TYPE_BASE_APPLICATION, dc, "w");
@@ -533,7 +530,7 @@
         assertEquals("Visible keyguard must influence device orientation",
                 SCREEN_ORIENTATION_PORTRAIT, dc.getOrientation());
 
-        sWm.setKeyguardGoingAway(true);
+        mWm.setKeyguardGoingAway(true);
         assertEquals("Keyguard that is going away must not influence device orientation",
                 SCREEN_ORIENTATION_LANDSCAPE, dc.getOrientation());
     }
@@ -543,10 +540,10 @@
         final DisplayContent dc = createNewDisplay();
 
         assertTrue(dc.mShouldOverrideDisplayConfiguration);
-        sWm.dontOverrideDisplayInfo(dc.getDisplayId());
+        mWm.dontOverrideDisplayInfo(dc.getDisplayId());
 
         assertFalse(dc.mShouldOverrideDisplayConfiguration);
-        verify(sWm.mDisplayManagerInternal, times(1))
+        verify(mWm.mDisplayManagerInternal, times(1))
                 .setDisplayInfoOverrideFromWindowManager(dc.getDisplayId(), null);
     }
 
@@ -572,7 +569,7 @@
     }
 
     private boolean isOptionsPanelAtRight(int displayId) {
-        return (sWm.getPreferredOptionsPanelGravity(displayId) & Gravity.RIGHT) == Gravity.RIGHT;
+        return (mWm.getPreferredOptionsPanelGravity(displayId) & Gravity.RIGHT) == Gravity.RIGHT;
     }
 
     private static void verifySizes(DisplayContent displayContent, int expectedBaseWidth,
@@ -583,8 +580,8 @@
     }
 
     private void updateFocusedWindow() {
-        synchronized (sWm.mGlobalLock) {
-            sWm.updateFocusedWindowLocked(UPDATE_FOCUS_NORMAL, false);
+        synchronized (mWm.mGlobalLock) {
+            mWm.updateFocusedWindowLocked(UPDATE_FOCUS_NORMAL, false);
         }
     }
 
diff --git a/services/tests/servicestests/src/com/android/server/wm/DisplaySettingsTests.java b/services/tests/servicestests/src/com/android/server/wm/DisplaySettingsTests.java
index 3be1258..f0c49c8 100644
--- a/services/tests/servicestests/src/com/android/server/wm/DisplaySettingsTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/DisplaySettingsTests.java
@@ -12,11 +12,12 @@
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
- *
  */
 
 package com.android.server.wm;
 
+import static androidx.test.platform.app.InstrumentationRegistry.getInstrumentation;
+
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotEquals;
@@ -31,15 +32,13 @@
 import android.view.DisplayInfo;
 import android.view.Surface;
 
-import androidx.test.InstrumentationRegistry;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.policy.WindowManagerPolicy;
 
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 import java.io.File;
 
@@ -47,14 +46,13 @@
  * Tests for the {@link DisplaySettings} class.
  *
  * Build/Install/Run:
- *  atest FrameworksServicesTests:com.android.server.wm.DisplaySettingsTests
+ *  atest FrameworksServicesTests:DisplaySettingsTests
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class DisplaySettingsTests extends WindowTestsBase {
 
-    private File mTestFolder;
+    private static final File TEST_FOLDER = getInstrumentation().getTargetContext().getCacheDir();
     private DisplaySettings mTarget;
 
     private DisplayContent mPrimaryDisplay;
@@ -62,21 +60,23 @@
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
+        deleteRecursively(TEST_FOLDER);
 
-        mTestFolder = InstrumentationRegistry.getContext().getCacheDir();
-        deleteRecursively(mTestFolder);
+        mWm.setSupportsFreeformWindowManagement(false);
+        mWm.setIsPc(false);
 
-        sWm.setSupportsFreeformWindowManagement(false);
-        sWm.setIsPc(false);
+        mTarget = new DisplaySettings(mWm, TEST_FOLDER);
 
-        mTarget = new DisplaySettings(sWm, mTestFolder);
-
-        mPrimaryDisplay = sWm.getDefaultDisplayContentLocked();
+        mPrimaryDisplay = mWm.getDefaultDisplayContentLocked();
         mSecondaryDisplay = mDisplayContent;
         assertNotEquals(Display.DEFAULT_DISPLAY, mSecondaryDisplay.getDisplayId());
     }
 
+    @After
+    public void tearDown() {
+        deleteRecursively(TEST_FOLDER);
+    }
+
     @Test
     public void testPrimaryDisplayDefaultToFullscreenWithoutFreeformSupport() {
         mTarget.applySettingsToDisplayLocked(mPrimaryDisplay);
@@ -87,7 +87,7 @@
 
     @Test
     public void testPrimaryDisplayDefaultToFullscreenWithFreeformSupportNonPc() {
-        sWm.setSupportsFreeformWindowManagement(true);
+        mWm.setSupportsFreeformWindowManagement(true);
 
         mTarget.applySettingsToDisplayLocked(mPrimaryDisplay);
 
@@ -97,8 +97,8 @@
 
     @Test
     public void testPrimaryDisplayDefaultToFreeformWithFreeformIsPc() {
-        sWm.setSupportsFreeformWindowManagement(true);
-        sWm.setIsPc(true);
+        mWm.setSupportsFreeformWindowManagement(true);
+        mWm.setIsPc(true);
 
         mTarget.applySettingsToDisplayLocked(mPrimaryDisplay);
 
@@ -116,7 +116,7 @@
 
     @Test
     public void testSecondaryDisplayDefaultToFreeformWithFreeformSupportNonPc() {
-        sWm.setSupportsFreeformWindowManagement(true);
+        mWm.setSupportsFreeformWindowManagement(true);
 
         mTarget.applySettingsToDisplayLocked(mSecondaryDisplay);
 
@@ -126,8 +126,8 @@
 
     @Test
     public void testSecondaryDisplayDefaultToFreeformWithFreeformSupportIsPc() {
-        sWm.setSupportsFreeformWindowManagement(true);
-        sWm.setIsPc(true);
+        mWm.setSupportsFreeformWindowManagement(true);
+        mWm.setIsPc(true);
 
         mTarget.applySettingsToDisplayLocked(mSecondaryDisplay);
 
@@ -157,7 +157,7 @@
         doAnswer(invocation -> {
             ((DisplayInfo) invocation.getArguments()[1]).copyFrom(originalInfo);
             return null;
-        }).when(sWm.mDisplayManagerInternal).getNonOverrideDisplayInfo(anyInt(), any());
+        }).when(mWm.mDisplayManagerInternal).getNonOverrideDisplayInfo(anyInt(), any());
 
         mTarget.setForcedSize(mSecondaryDisplay, 1000 /* width */, 2000 /* height */);
         applySettingsToDisplayByNewInstance(mSecondaryDisplay);
@@ -165,7 +165,7 @@
         assertEquals(1000 /* width */, mSecondaryDisplay.mBaseDisplayWidth);
         assertEquals(2000 /* height */, mSecondaryDisplay.mBaseDisplayHeight);
 
-        sWm.clearForcedDisplaySize(mSecondaryDisplay.getDisplayId());
+        mWm.clearForcedDisplaySize(mSecondaryDisplay.getDisplayId());
         assertEquals(mSecondaryDisplay.mInitialDisplayWidth, mSecondaryDisplay.mBaseDisplayWidth);
         assertEquals(mSecondaryDisplay.mInitialDisplayHeight, mSecondaryDisplay.mBaseDisplayHeight);
     }
@@ -177,7 +177,7 @@
 
         assertEquals(600 /* density */, mSecondaryDisplay.mBaseDisplayDensity);
 
-        sWm.clearForcedDisplayDensityForUser(mSecondaryDisplay.getDisplayId(), 0 /* userId */);
+        mWm.clearForcedDisplayDensityForUser(mSecondaryDisplay.getDisplayId(), 0 /* userId */);
         assertEquals(mSecondaryDisplay.mInitialDisplayDensity,
                 mSecondaryDisplay.mBaseDisplayDensity);
     }
@@ -189,7 +189,7 @@
 
         assertTrue(mSecondaryDisplay.mDisplayScalingDisabled);
 
-        sWm.setForcedDisplayScalingMode(mSecondaryDisplay.getDisplayId(),
+        mWm.setForcedDisplayScalingMode(mSecondaryDisplay.getDisplayId(),
                 DisplayContent.FORCE_SCALING_MODE_AUTO);
         assertFalse(mSecondaryDisplay.mDisplayScalingDisabled);
     }
@@ -298,20 +298,20 @@
      * that also means the previous state must be written correctly.
      */
     private void applySettingsToDisplayByNewInstance(DisplayContent display) {
-        new DisplaySettings(sWm, mTestFolder).applySettingsToDisplayLocked(display);
+        new DisplaySettings(mWm, TEST_FOLDER).applySettingsToDisplayLocked(display);
     }
 
     private static boolean deleteRecursively(File file) {
+        boolean fullyDeleted = true;
         if (file.isFile()) {
             return file.delete();
+        } else if (file.isDirectory()) {
+            final File[] files = file.listFiles();
+            for (File child : files) {
+                fullyDeleted &= deleteRecursively(child);
+            }
+            fullyDeleted &= file.delete();
         }
-
-        boolean fullyDeleted = true;
-        final File[] files = file.listFiles();
-        for (File child : files) {
-            fullyDeleted &= deleteRecursively(child);
-        }
-        fullyDeleted &= file.delete();
         return fullyDeleted;
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/DragDropControllerTests.java b/services/tests/servicestests/src/com/android/server/wm/DragDropControllerTests.java
index 31b2fef..55e766d 100644
--- a/services/tests/servicestests/src/com/android/server/wm/DragDropControllerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/DragDropControllerTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -40,23 +40,24 @@
 import android.view.SurfaceSession;
 import android.view.View;
 
-import com.android.internal.annotations.GuardedBy;
+import androidx.test.filters.SmallTest;
+
 import com.android.server.LocalServices;
 
 import org.junit.After;
+import org.junit.AfterClass;
 import org.junit.Before;
+import org.junit.BeforeClass;
 import org.junit.Test;
 
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 
-import androidx.test.filters.SmallTest;
-
 /**
  * Tests for the {@link DragDropController} class.
  *
  * Build/Install/Run:
- *  atest FrameworksServicesTests:com.android.server.wm.DragDropControllerTests
+ *  atest FrameworksServicesTests:DragDropControllerTests
  */
 @SmallTest
 @Presubmit
@@ -67,7 +68,6 @@
     private IBinder mToken;
 
     static class TestDragDropController extends DragDropController {
-        @GuardedBy("sWm.mWindowMap")
         private Runnable mCloseCallback;
 
         TestDragDropController(WindowManagerService service, Looper looper) {
@@ -107,31 +107,34 @@
         return window;
     }
 
-    @Override
-    @Before
-    public void setUp() throws Exception {
+    @BeforeClass
+    public static void setUpOnce() {
         final UserManagerInternal userManager = mock(UserManagerInternal.class);
         LocalServices.addService(UserManagerInternal.class, userManager);
+    }
 
-        super.setUp();
+    @AfterClass
+    public static void tearDownOnce() {
+        LocalServices.removeServiceForTest(UserManagerInternal.class);
+    }
 
-        mTarget = new TestDragDropController(sWm, sWm.mH.getLooper());
+    @Before
+    public void setUp() throws Exception {
+        mTarget = new TestDragDropController(mWm, mWm.mH.getLooper());
         mDisplayContent = spy(mDisplayContent);
         mWindow = createDropTargetWindow("Drag test window", 0);
         doReturn(mWindow).when(mDisplayContent).getTouchableWinAtPointLocked(0, 0);
-        when(sWm.mInputManager.transferTouchFocus(any(), any())).thenReturn(true);
+        when(mWm.mInputManager.transferTouchFocus(any(), any())).thenReturn(true);
 
-        synchronized (sWm.mGlobalLock) {
-            sWm.mWindowMap.put(mWindow.mClient.asBinder(), mWindow);
+        synchronized (mWm.mGlobalLock) {
+            mWm.mWindowMap.put(mWindow.mClient.asBinder(), mWindow);
         }
     }
 
-    @Override
     @After
     public void tearDown() throws Exception {
-        LocalServices.removeServiceForTest(UserManagerInternal.class);
         final CountDownLatch latch;
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             if (!mTarget.dragDropActiveLocked()) {
                 return;
             }
@@ -142,8 +145,6 @@
             mTarget.setOnClosedCallbackLocked(latch::countDown);
         }
         assertTrue(latch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
-
-        super.tearDown();
     }
 
     @Test
@@ -174,7 +175,7 @@
                     .setFormat(PixelFormat.TRANSLUCENT)
                     .build();
 
-            assertTrue(sWm.mInputManager.transferTouchFocus(null, null));
+            assertTrue(mWm.mInputManager.transferTouchFocus(null, null));
             mToken = mTarget.performDrag(
                     new SurfaceSession(), 0, 0, mWindow.mClient, flag, surface, 0, 0, 0, 0, 0,
                     data);
diff --git a/services/tests/servicestests/src/com/android/server/wm/PinnedStackControllerTest.java b/services/tests/servicestests/src/com/android/server/wm/PinnedStackControllerTest.java
index 7222a99..1fae317 100644
--- a/services/tests/servicestests/src/com/android/server/wm/PinnedStackControllerTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/PinnedStackControllerTest.java
@@ -1,3 +1,19 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package com.android.server.wm;
 
 import static android.view.Display.DEFAULT_DISPLAY;
@@ -16,17 +32,18 @@
 import android.view.IPinnedStackListener;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
+/**
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:PinnedStackControllerTest
+ */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class PinnedStackControllerTest extends WindowTestsBase {
 
     @Mock private IPinnedStackListener mIPinnedStackListener;
@@ -34,15 +51,15 @@
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
         MockitoAnnotations.initMocks(this);
+
         when(mIPinnedStackListener.asBinder()).thenReturn(mIPinnedStackListenerStub);
     }
 
     @Test
     public void setShelfHeight_shelfVisibilityChangedTriggered() throws RemoteException {
-        sWm.mSupportsPictureInPicture = true;
-        sWm.registerPinnedStackListener(DEFAULT_DISPLAY, mIPinnedStackListener);
+        mWm.mSupportsPictureInPicture = true;
+        mWm.registerPinnedStackListener(DEFAULT_DISPLAY, mIPinnedStackListener);
 
         verify(mIPinnedStackListener).onImeVisibilityChanged(false, 0);
         verify(mIPinnedStackListener).onShelfVisibilityChanged(false, 0);
@@ -55,7 +72,7 @@
 
         final int SHELF_HEIGHT = 300;
 
-        sWm.setShelfHeight(true, SHELF_HEIGHT);
+        mWm.setShelfHeight(true, SHELF_HEIGHT);
         verify(mIPinnedStackListener).onShelfVisibilityChanged(true, SHELF_HEIGHT);
         verify(mIPinnedStackListener).onMovementBoundsChanged(any(), any(), any(), eq(false),
                 eq(true), anyInt());
diff --git a/services/tests/servicestests/src/com/android/server/wm/RecentsAnimationControllerTest.java b/services/tests/servicestests/src/com/android/server/wm/RecentsAnimationControllerTest.java
index 088e229..fe5fc06 100644
--- a/services/tests/servicestests/src/com/android/server/wm/RecentsAnimationControllerTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/RecentsAnimationControllerTest.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -24,9 +24,9 @@
 import static com.android.server.wm.RecentsAnimationController.REORDER_KEEP_IN_PLACE;
 import static com.android.server.wm.RecentsAnimationController.REORDER_MOVE_TO_ORIGINAL_POSITION;
 
-import static org.junit.Assert.fail;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.atLeast;
 import static org.mockito.Mockito.verify;
@@ -42,22 +42,20 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.wm.SurfaceAnimator.OnAnimationFinishedCallback;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
 /**
- * atest FrameworksServicesTests:com.android.server.wm.RecentsAnimationControllerTest
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:RecentsAnimationControllerTest
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class RecentsAnimationControllerTest extends WindowTestsBase {
 
     @Mock SurfaceControl mMockLeash;
@@ -69,10 +67,10 @@
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
         MockitoAnnotations.initMocks(this);
+
         when(mMockRunner.asBinder()).thenReturn(new Binder());
-        mController = new RecentsAnimationController(sWm, mMockRunner, mAnimationCallbacks,
+        mController = new RecentsAnimationController(mWm, mMockRunner, mAnimationCallbacks,
                 DEFAULT_DISPLAY);
     }
 
@@ -96,7 +94,7 @@
     }
 
     @Test
-    public void testCancelAfterRemove_expectIgnored() throws Exception {
+    public void testCancelAfterRemove_expectIgnored() {
         final AppWindowToken appWindow = createAppWindowToken(mDisplayContent,
                 WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD);
         AnimationAdapter adapter = mController.addAnimation(appWindow.getTask(),
@@ -114,10 +112,10 @@
         }
     }
 
-    @Test
     @FlakyTest(bugId = 117117823)
-    public void testIncludedApps_expectTargetAndVisible() throws Exception {
-        sWm.setRecentsAnimationController(mController);
+    @Test
+    public void testIncludedApps_expectTargetAndVisible() {
+        mWm.setRecentsAnimationController(mController);
         final AppWindowToken homeAppWindow = createAppWindowToken(mDisplayContent,
                 WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_HOME);
         final AppWindowToken appWindow = createAppWindowToken(mDisplayContent,
diff --git a/services/tests/servicestests/src/com/android/server/wm/RemoteAnimationControllerTest.java b/services/tests/servicestests/src/com/android/server/wm/RemoteAnimationControllerTest.java
index ae92984..fa53795 100644
--- a/services/tests/servicestests/src/com/android/server/wm/RemoteAnimationControllerTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/RemoteAnimationControllerTest.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -39,7 +39,6 @@
 import android.view.SurfaceControl.Transaction;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.testutils.OffsettableClock;
 import com.android.server.testutils.TestHandler;
@@ -47,17 +46,16 @@
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
 /**
- * atest FrameworksServicesTests:com.android.server.wm.RemoteAnimationControllerTest
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:RemoteAnimationControllerTest
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class RemoteAnimationControllerTest extends WindowTestsBase {
 
     @Mock SurfaceControl mMockLeash;
@@ -71,15 +69,13 @@
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
         MockitoAnnotations.initMocks(this);
+
         when(mMockRunner.asBinder()).thenReturn(new Binder());
         mAdapter = new RemoteAnimationAdapter(mMockRunner, 100, 50);
         mAdapter.setCallingPid(123);
-        sWm.mH.runWithScissors(() -> {
-            mHandler = new TestHandler(null, mClock);
-        }, 0);
-        mController = new RemoteAnimationController(sWm, mAdapter, mHandler);
+        mWm.mH.runWithScissors(() -> mHandler = new TestHandler(null, mClock), 0);
+        mController = new RemoteAnimationController(mWm, mAdapter, mHandler);
     }
 
     @Test
@@ -91,7 +87,7 @@
                     new Point(50, 100), new Rect(50, 100, 150, 150));
             adapter.startAnimation(mMockLeash, mMockTransaction, mFinishedCallback);
             mController.goodToGo();
-            sWm.mAnimator.executeAfterPrepareSurfacesRunnables();
+            mWm.mAnimator.executeAfterPrepareSurfacesRunnables();
             final ArgumentCaptor<RemoteAnimationTarget[]> appsCaptor =
                     ArgumentCaptor.forClass(RemoteAnimationTarget[].class);
             final ArgumentCaptor<IRemoteAnimationFinishedCallback> finishedCaptor =
@@ -146,7 +142,7 @@
 
     @Test
     public void testTimeout_scaled() throws Exception {
-        sWm.setAnimationScale(2, 5.0f);
+        mWm.setAnimationScale(2, 5.0f);
         try{
             final WindowState win = createWindow(null /* parent */, TYPE_BASE_APPLICATION, "testWin");
             final AnimationAdapter adapter = mController.createAnimationAdapter(win.mAppToken,
@@ -165,19 +161,19 @@
             verify(mMockRunner).onAnimationCancelled();
             verify(mFinishedCallback).onAnimationFinished(eq(adapter));
         } finally {
-            sWm.setAnimationScale(2, 1.0f);
+            mWm.setAnimationScale(2, 1.0f);
         }
 
     }
 
     @Test
-    public void testZeroAnimations() throws Exception {
+    public void testZeroAnimations() {
         mController.goodToGo();
         verifyNoMoreInteractionsExceptAsBinder(mMockRunner);
     }
 
     @Test
-    public void testNotReallyStarted() throws Exception {
+    public void testNotReallyStarted() {
         final WindowState win = createWindow(null /* parent */, TYPE_BASE_APPLICATION, "testWin");
         mController.createAnimationAdapter(win.mAppToken,
                 new Point(50, 100), new Rect(50, 100, 150, 150));
@@ -195,7 +191,7 @@
                 new Point(50, 100), new Rect(50, 100, 150, 150));
         adapter.startAnimation(mMockLeash, mMockTransaction, mFinishedCallback);
         mController.goodToGo();
-        sWm.mAnimator.executeAfterPrepareSurfacesRunnables();
+        mWm.mAnimator.executeAfterPrepareSurfacesRunnables();
         final ArgumentCaptor<RemoteAnimationTarget[]> appsCaptor =
                 ArgumentCaptor.forClass(RemoteAnimationTarget[].class);
         final ArgumentCaptor<IRemoteAnimationFinishedCallback> finishedCaptor =
@@ -206,7 +202,7 @@
     }
 
     @Test
-    public void testRemovedBeforeStarted() throws Exception {
+    public void testRemovedBeforeStarted() {
         final WindowState win = createWindow(null /* parent */, TYPE_BASE_APPLICATION, "testWin");
         final AnimationAdapter adapter = mController.createAnimationAdapter(win.mAppToken,
                 new Point(50, 100), new Rect(50, 100, 150, 150));
diff --git a/services/tests/servicestests/src/com/android/server/wm/RootWindowContainerTests.java b/services/tests/servicestests/src/com/android/server/wm/RootWindowContainerTests.java
index 001bed9..62a617d 100644
--- a/services/tests/servicestests/src/com/android/server/wm/RootWindowContainerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/RootWindowContainerTests.java
@@ -1,30 +1,43 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package com.android.server.wm;
 
-import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertEquals;
 
 import android.content.res.Configuration;
 import android.graphics.Rect;
 import android.platform.test.annotations.Presubmit;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Tests for the {@link RootWindowContainer} class.
  *
  * Build/Install/Run:
- *  atest FrameworksServicesTests:com.android.server.wm.RootWindowContainerTests
+ *  atest FrameworksServicesTests:RootWindowContainerTests
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class RootWindowContainerTests extends WindowTestsBase {
     @Test
-    public void testSetDisplayOverrideConfigurationIfNeeded() throws Exception {
-        synchronized (sWm.mGlobalLock) {
+    public void testSetDisplayOverrideConfigurationIfNeeded() {
+        synchronized (mWm.mGlobalLock) {
             // Add first stack we expect to be updated with configuration change.
             final TaskStack stack = createTaskStackOnDisplay(mDisplayContent);
             stack.getOverrideConfiguration().windowConfiguration.setBounds(new Rect(0, 0, 5, 5));
@@ -41,12 +54,12 @@
             override.windowConfiguration.setBounds(new Rect(0, 0, 10, 10));
 
             // Set display override.
-            final int[] results = sWm.mRoot.setDisplayOverrideConfigurationIfNeeded(override,
+            final int[] results = mWm.mRoot.setDisplayOverrideConfigurationIfNeeded(override,
                     mDisplayContent.getDisplayId());
 
             // Ensure only first stack is returned.
-            assertTrue(results.length == 1);
-            assertTrue(results[0] == stack.mStackId);
+            assertEquals(1, results.length);
+            assertEquals(stack.mStackId, results[0]);
         }
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/StackWindowControllerTests.java b/services/tests/servicestests/src/com/android/server/wm/StackWindowControllerTests.java
index 9f2645c..ce5b13c 100644
--- a/services/tests/servicestests/src/com/android/server/wm/StackWindowControllerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/StackWindowControllerTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -25,10 +25,8 @@
 import android.platform.test.annotations.Presubmit;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Test class for {@link StackWindowController}.
@@ -38,10 +36,9 @@
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class StackWindowControllerTests extends WindowTestsBase {
     @Test
-    public void testRemoveContainer() throws Exception {
+    public void testRemoveContainer() {
         final StackWindowController stackController =
                 createStackControllerOnDisplay(mDisplayContent);
         final WindowTestUtils.TestTaskWindowContainerController taskController =
@@ -61,7 +58,7 @@
     }
 
     @Test
-    public void testRemoveContainer_deferRemoval() throws Exception {
+    public void testRemoveContainer_deferRemoval() {
         final StackWindowController stackController =
                 createStackControllerOnDisplay(mDisplayContent);
         final WindowTestUtils.TestTaskWindowContainerController taskController =
@@ -87,7 +84,7 @@
     }
 
     @Test
-    public void testReparent() throws Exception {
+    public void testReparent() {
         // Create first stack on primary display.
         final StackWindowController stack1Controller =
                 createStackControllerOnDisplay(mDisplayContent);
diff --git a/services/tests/servicestests/src/com/android/server/wm/SurfaceAnimationRunnerTest.java b/services/tests/servicestests/src/com/android/server/wm/SurfaceAnimationRunnerTest.java
index 4551c36..584f269 100644
--- a/services/tests/servicestests/src/com/android/server/wm/SurfaceAnimationRunnerTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/SurfaceAnimationRunnerTest.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -27,6 +27,8 @@
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
+import static java.util.concurrent.TimeUnit.SECONDS;
+
 import android.animation.AnimationHandler.AnimationFrameCallbackProvider;
 import android.animation.ValueAnimator;
 import android.graphics.Matrix;
@@ -42,30 +44,27 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.wm.LocalAnimationAdapter.AnimationSpec;
 
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
 import org.mockito.junit.MockitoJUnit;
 import org.mockito.junit.MockitoRule;
 
-import static java.util.concurrent.TimeUnit.SECONDS;
-
 import java.util.concurrent.CountDownLatch;
 
 /**
  * Test class for {@link SurfaceAnimationRunner}.
  *
- * atest FrameworksServicesTests:com.android.server.wm.SurfaceAnimationRunnerTest
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:SurfaceAnimationRunnerTest
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class SurfaceAnimationRunnerTest extends WindowTestsBase {
 
     @Mock SurfaceControl mMockSurface;
@@ -79,7 +78,8 @@
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
+        MockitoAnnotations.initMocks(this);
+
         mFinishCallbackLatch = new CountDownLatch(1);
         mSurfaceAnimationRunner = new SurfaceAnimationRunner(null /* callbackProvider */, null,
                 mMockTransaction, mMockPowerManager);
@@ -112,7 +112,7 @@
     }
 
     @Test
-    public void testCancel_notStarted() throws Exception {
+    public void testCancel_notStarted() {
         mSurfaceAnimationRunner = new SurfaceAnimationRunner(new NoOpFrameCallbackProvider(), null,
                 mMockTransaction, mMockPowerManager);
         mSurfaceAnimationRunner
diff --git a/services/tests/servicestests/src/com/android/server/wm/SurfaceAnimatorTest.java b/services/tests/servicestests/src/com/android/server/wm/SurfaceAnimatorTest.java
index 7b5e8de..6833dc5 100644
--- a/services/tests/servicestests/src/com/android/server/wm/SurfaceAnimatorTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/SurfaceAnimatorTest.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -35,14 +35,13 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.wm.SurfaceAnimator.Animatable;
 import com.android.server.wm.SurfaceAnimator.OnAnimationFinishedCallback;
 
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
@@ -50,11 +49,11 @@
 /**
  * Test class for {@link SurfaceAnimatorTest}.
  *
- * atest FrameworksServicesTests:com.android.server.wm.SurfaceAnimatorTest
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:SurfaceAnimatorTest
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class SurfaceAnimatorTest extends WindowTestsBase {
 
     @Mock AnimationAdapter mSpec;
@@ -68,15 +67,24 @@
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
         MockitoAnnotations.initMocks(this);
-        mAnimatable = new MyAnimatable();
-        mAnimatable2 = new MyAnimatable();
-        mDeferFinishAnimatable = new DeferFinishAnimatable();
+
+        mAnimatable = new MyAnimatable(mWm, mSession, mTransaction);
+        mAnimatable2 = new MyAnimatable(mWm, mSession, mTransaction);
+        mDeferFinishAnimatable = new DeferFinishAnimatable(mWm, mSession, mTransaction);
+    }
+
+    @After
+    public void tearDown() {
+        mAnimatable = null;
+        mAnimatable2 = null;
+        mDeferFinishAnimatable = null;
+        mSession.kill();
+        mSession = null;
     }
 
     @Test
-    public void testRunAnimation() throws Exception {
+    public void testRunAnimation() {
         mAnimatable.mSurfaceAnimator.startAnimation(mTransaction, mSpec, true /* hidden */);
         final ArgumentCaptor<OnAnimationFinishedCallback> callbackCaptor = ArgumentCaptor.forClass(
                 OnAnimationFinishedCallback.class);
@@ -92,7 +100,7 @@
     }
 
     @Test
-    public void testOverrideAnimation() throws Exception {
+    public void testOverrideAnimation() {
         mAnimatable.mSurfaceAnimator.startAnimation(mTransaction, mSpec, true /* hidden */);
         final SurfaceControl firstLeash = mAnimatable.mLeash;
         mAnimatable.mSurfaceAnimator.startAnimation(mTransaction, mSpec2, true /* hidden */);
@@ -117,7 +125,7 @@
     }
 
     @Test
-    public void testCancelAnimation() throws Exception {
+    public void testCancelAnimation() {
         mAnimatable.mSurfaceAnimator.startAnimation(mTransaction, mSpec, true /* hidden */);
         assertAnimating(mAnimatable);
         mAnimatable.mSurfaceAnimator.cancelAnimation();
@@ -128,7 +136,7 @@
     }
 
     @Test
-    public void testDelayingAnimationStart() throws Exception {
+    public void testDelayingAnimationStart() {
         mAnimatable.mSurfaceAnimator.startDelayingAnimationStart();
         mAnimatable.mSurfaceAnimator.startAnimation(mTransaction, mSpec, true /* hidden */);
         verifyZeroInteractions(mSpec);
@@ -139,7 +147,7 @@
     }
 
     @Test
-    public void testDelayingAnimationStartAndCancelled() throws Exception {
+    public void testDelayingAnimationStartAndCancelled() {
         mAnimatable.mSurfaceAnimator.startDelayingAnimationStart();
         mAnimatable.mSurfaceAnimator.startAnimation(mTransaction, mSpec, true /* hidden */);
         mAnimatable.mSurfaceAnimator.cancelAnimation();
@@ -150,7 +158,7 @@
     }
 
     @Test
-    public void testTransferAnimation() throws Exception {
+    public void testTransferAnimation() {
         mAnimatable.mSurfaceAnimator.startAnimation(mTransaction, mSpec, true /* hidden */);
 
         final ArgumentCaptor<OnAnimationFinishedCallback> callbackCaptor = ArgumentCaptor.forClass(
@@ -171,7 +179,7 @@
 
     @Test
     @FlakyTest(detail = "Promote once confirmed non-flaky")
-    public void testDeferFinish() throws Exception {
+    public void testDeferFinish() {
 
         // Start animation
         mDeferFinishAnimatable.mSurfaceAnimator.startAnimation(mTransaction, mSpec,
@@ -186,7 +194,7 @@
         assertAnimating(mDeferFinishAnimatable);
 
         // Now end defer finishing.
-        mDeferFinishAnimatable.endDeferFinishCallback.run();
+        mDeferFinishAnimatable.mEndDeferFinishCallback.run();
         assertNotAnimating(mAnimatable2);
         assertTrue(mDeferFinishAnimatable.mFinishedCallbackCalled);
         verify(mTransaction).destroy(eq(mDeferFinishAnimatable.mLeash));
@@ -202,26 +210,30 @@
         assertNull(animatable.mSurfaceAnimator.getAnimation());
     }
 
-    private class MyAnimatable implements Animatable {
+    private static class MyAnimatable implements Animatable {
 
+        private final SurfaceSession mSession;
+        private final Transaction mTransaction;
         final SurfaceControl mParent;
         final SurfaceControl mSurface;
         final SurfaceAnimator mSurfaceAnimator;
         SurfaceControl mLeash;
         boolean mFinishedCallbackCalled;
 
-        MyAnimatable() {
-            mParent = sWm.makeSurfaceBuilder(mSession)
+        MyAnimatable(WindowManagerService wm, SurfaceSession session, Transaction transaction) {
+            mSession = session;
+            mTransaction = transaction;
+            mParent = wm.makeSurfaceBuilder(mSession)
                     .setName("test surface parent")
                     .setSize(3000, 3000)
                     .build();
-            mSurface = sWm.makeSurfaceBuilder(mSession)
+            mSurface = wm.makeSurfaceBuilder(mSession)
                     .setName("test surface")
                     .setSize(1, 1)
                     .build();
             mFinishedCallbackCalled = false;
             mLeash = null;
-            mSurfaceAnimator = new SurfaceAnimator(this, mFinishedCallback, sWm);
+            mSurfaceAnimator = new SurfaceAnimator(this, mFinishedCallback, wm);
         }
 
         @Override
@@ -281,13 +293,18 @@
         private final Runnable mFinishedCallback = () -> mFinishedCallbackCalled = true;
     }
 
-    private class DeferFinishAnimatable extends MyAnimatable {
+    private static class DeferFinishAnimatable extends MyAnimatable {
 
-        Runnable endDeferFinishCallback;
+        Runnable mEndDeferFinishCallback;
+
+        DeferFinishAnimatable(WindowManagerService wm, SurfaceSession session,
+                Transaction transaction) {
+            super(wm, session, transaction);
+        }
 
         @Override
         public boolean shouldDeferAnimationFinish(Runnable endDeferFinishCallback) {
-            this.endDeferFinishCallback = endDeferFinishCallback;
+            mEndDeferFinishCallback = endDeferFinishCallback;
             return true;
         }
     }
diff --git a/services/tests/servicestests/src/com/android/server/wm/TaskPositionerTests.java b/services/tests/servicestests/src/com/android/server/wm/TaskPositionerTests.java
index 17b7fc1..785b955 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskPositionerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskPositionerTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -35,24 +35,22 @@
 import android.view.Display;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 import org.mockito.Mockito;
 
 /**
  * Tests for the {@link TaskPositioner} class.
  *
- * runtest frameworks-services -c com.android.server.wm.TaskPositionerTests
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:TaskPositionerTests
  */
 @SmallTest
-@RunWith(AndroidJUnit4.class)
 public class TaskPositionerTests extends WindowTestsBase {
 
-    private final boolean DEBUGGING = false;
-    private final String TAG = "TaskPositionerTest";
+    private static final boolean DEBUGGING = false;
+    private static final String TAG = "TaskPositionerTest";
 
     private final static int MOUSE_DELTA_X = 5;
     private final static int MOUSE_DELTA_Y = 5;
@@ -65,8 +63,6 @@
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
-
         TaskPositioner.setFactory(null);
 
         final Display display = mDisplayContent.getDisplay();
@@ -77,7 +73,7 @@
         mMinVisibleWidth = dipToPixel(MINIMUM_VISIBLE_WIDTH_IN_DP, dm);
         mMinVisibleHeight = dipToPixel(MINIMUM_VISIBLE_HEIGHT_IN_DP, dm);
 
-        mPositioner = new TaskPositioner(sWm, Mockito.mock(IActivityTaskManager.class));
+        mPositioner = new TaskPositioner(mWm, Mockito.mock(IActivityTaskManager.class));
         mPositioner.register(mDisplayContent);
 
         mWindow = Mockito.spy(createWindow(null, TYPE_BASE_APPLICATION, "window"));
@@ -94,7 +90,7 @@
     }
 
     @Test
-    public void testOverrideFactory() throws Exception {
+    public void testOverrideFactory() {
         final boolean[] created = new boolean[1];
         created[0] = false;
         TaskPositioner.setFactory(new TaskPositioner.Factory() {
@@ -105,7 +101,7 @@
             }
         });
 
-        assertNull(TaskPositioner.create(sWm));
+        assertNull(TaskPositioner.create(mWm));
         assertTrue(created[0]);
     }
 
@@ -114,7 +110,7 @@
      * as does some basic tests (e.g. dragging in Y only will keep X stable).
      */
     @Test
-    public void testBasicFreeWindowResizing() throws Exception {
+    public void testBasicFreeWindowResizing() {
         final Rect r = new Rect(100, 220, 700, 520);
         final int midY = (r.top + r.bottom) / 2;
         mDimBounds.set(r);
@@ -175,7 +171,7 @@
      * This tests that by dragging any edge, the fixed / opposite edge(s) remains anchored.
      */
     @Test
-    public void testFreeWindowResizingTestAllEdges() throws Exception {
+    public void testFreeWindowResizingTestAllEdges() {
         final Rect r = new Rect(100, 220, 700, 520);
         final int midX = (r.left + r.right) / 2;
         final int midY = (r.top + r.bottom) / 2;
@@ -260,7 +256,7 @@
      * right things upon resizing when dragged from the top left corner.
      */
     @Test
-    public void testLandscapePreservedWindowResizingDragTopLeft() throws Exception {
+    public void testLandscapePreservedWindowResizingDragTopLeft() {
         final Rect r = new Rect(100, 220, 700, 520);
         mDimBounds.set(r);
 
@@ -298,7 +294,7 @@
      * right things upon resizing when dragged from the left corner.
      */
     @Test
-    public void testLandscapePreservedWindowResizingDragLeft() throws Exception {
+    public void testLandscapePreservedWindowResizingDragLeft() {
         final Rect r = new Rect(100, 220, 700, 520);
         final int midY = (r.top + r.bottom) / 2;
         mDimBounds.set(r);
@@ -339,7 +335,7 @@
      * right things upon resizing when dragged from the top corner.
      */
     @Test
-    public void testLandscapePreservedWindowResizingDragTop() throws Exception {
+    public void testLandscapePreservedWindowResizingDragTop() {
         final Rect r = new Rect(100, 220, 700, 520);
         final int midX = (r.left + r.right) / 2;
         mDimBounds.set(r);
@@ -376,7 +372,7 @@
      * right things upon resizing when dragged from the top left corner.
      */
     @Test
-    public void testPortraitPreservedWindowResizingDragTopLeft() throws Exception {
+    public void testPortraitPreservedWindowResizingDragTopLeft() {
         final Rect r = new Rect(330, 100, 630, 600);
         mDimBounds.set(r);
 
@@ -409,7 +405,7 @@
      * right things upon resizing when dragged from the left corner.
      */
     @Test
-    public void testPortraitPreservedWindowResizingDragLeft() throws Exception {
+    public void testPortraitPreservedWindowResizingDragLeft() {
         final Rect r = new Rect(330, 100, 630, 600);
         final int midY = (r.top + r.bottom) / 2;
         mDimBounds.set(r);
@@ -452,7 +448,7 @@
      * right things upon resizing when dragged from the top corner.
      */
     @Test
-    public void testPortraitPreservedWindowResizingDragTop() throws Exception {
+    public void testPortraitPreservedWindowResizingDragTop() {
         final Rect r = new Rect(330, 100, 630, 600);
         final int midX = (r.left + r.right) / 2;
         mDimBounds.set(r);
@@ -485,7 +481,7 @@
                 mPositioner.getWindowDragBounds());
     }
 
-    private void assertBoundsEquals(Rect expected, Rect actual) {
+    private static void assertBoundsEquals(Rect expected, Rect actual) {
         if (DEBUGGING) {
             if (!expected.equals(actual)) {
                 Log.e(TAG, "rect(" + actual.toString() + ") != isRect(" + actual.toString()
diff --git a/services/tests/servicestests/src/com/android/server/wm/TaskPositioningControllerTests.java b/services/tests/servicestests/src/com/android/server/wm/TaskPositioningControllerTests.java
index d1480c5..00b4629 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskPositioningControllerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskPositioningControllerTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -32,70 +32,66 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Tests for the {@link TaskPositioningController} class.
  *
- * atest com.android.server.wm.TaskPositioningControllerTests
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:TaskPositioningControllerTests
  */
-@SmallTest
 @FlakyTest(bugId = 117924387)
-@RunWith(AndroidJUnit4.class)
+@SmallTest
 @Presubmit
 public class TaskPositioningControllerTests extends WindowTestsBase {
     private static final int TIMEOUT_MS = 1000;
+
     private TaskPositioningController mTarget;
     private WindowState mWindow;
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
+        assertNotNull(mWm.mTaskPositioningController);
+        mTarget = mWm.mTaskPositioningController;
 
-        assertNotNull(sWm.mTaskPositioningController);
-        mTarget = sWm.mTaskPositioningController;
-
-        when(sWm.mInputManager.transferTouchFocus(
+        when(mWm.mInputManager.transferTouchFocus(
                 any(InputChannel.class),
                 any(InputChannel.class))).thenReturn(true);
 
         mWindow = createWindow(null, TYPE_BASE_APPLICATION, "window");
         mWindow.mInputChannel = new InputChannel();
-        synchronized (sWm.mGlobalLock) {
-            sWm.mWindowMap.put(mWindow.mClient.asBinder(), mWindow);
+        synchronized (mWm.mGlobalLock) {
+            mWm.mWindowMap.put(mWindow.mClient.asBinder(), mWindow);
         }
     }
 
     @Test
-    public void testStartAndFinishPositioning() throws Exception {
-        synchronized (sWm.mGlobalLock) {
+    public void testStartAndFinishPositioning() {
+        synchronized (mWm.mGlobalLock) {
             assertFalse(mTarget.isPositioningLocked());
             assertNull(mTarget.getDragWindowHandleLocked());
         }
 
         assertTrue(mTarget.startMovingTask(mWindow.mClient, 0, 0));
 
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             assertTrue(mTarget.isPositioningLocked());
             assertNotNull(mTarget.getDragWindowHandleLocked());
         }
 
         mTarget.finishTaskPositioning();
         // Wait until the looper processes finishTaskPositioning.
-        assertTrue(sWm.mH.runWithScissors(() -> {}, TIMEOUT_MS));
+        assertTrue(mWm.mH.runWithScissors(() -> { }, TIMEOUT_MS));
 
         assertFalse(mTarget.isPositioningLocked());
         assertNull(mTarget.getDragWindowHandleLocked());
     }
 
     @Test
-    public void testHandleTapOutsideTask() throws Exception {
-        synchronized (sWm.mGlobalLock) {
-
+    public void testHandleTapOutsideTask() {
+        synchronized (mWm.mGlobalLock) {
             assertFalse(mTarget.isPositioningLocked());
             assertNull(mTarget.getDragWindowHandleLocked());
         }
@@ -106,16 +102,16 @@
 
         mTarget.handleTapOutsideTask(content, 0, 0);
         // Wait until the looper processes finishTaskPositioning.
-        assertTrue(sWm.mH.runWithScissors(() -> {}, TIMEOUT_MS));
+        assertTrue(mWm.mH.runWithScissors(() -> { }, TIMEOUT_MS));
 
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             assertTrue(mTarget.isPositioningLocked());
             assertNotNull(mTarget.getDragWindowHandleLocked());
         }
 
         mTarget.finishTaskPositioning();
         // Wait until the looper processes finishTaskPositioning.
-        assertTrue(sWm.mH.runWithScissors(() -> {}, TIMEOUT_MS));
+        assertTrue(mWm.mH.runWithScissors(() -> { }, TIMEOUT_MS));
 
         assertFalse(mTarget.isPositioningLocked());
         assertNull(mTarget.getDragWindowHandleLocked());
diff --git a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotCacheTest.java b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotCacheTest.java
index c9d8004..1c6afd54 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotCacheTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotCacheTest.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -24,32 +24,32 @@
 import android.platform.test.annotations.Presubmit;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Test class for {@link TaskSnapshotCache}.
  *
- * runtest frameworks-services -c com.android.server.wm.TaskSnapshotCacheTest
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:TaskSnapshotCacheTest
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class TaskSnapshotCacheTest extends TaskSnapshotPersisterTestBase {
 
     private TaskSnapshotCache mCache;
 
+    @Override
     @Before
-    public void setUp() throws Exception {
+    public void setUp() {
         super.setUp();
-        mCache = new TaskSnapshotCache(sWm, mLoader);
+
+        mCache = new TaskSnapshotCache(mWm, mLoader);
     }
 
     @Test
-    public void testAppRemoved() throws Exception {
+    public void testAppRemoved() {
         final WindowState window = createWindow(null, FIRST_APPLICATION_WINDOW, "window");
         mCache.putSnapshot(window.getTask(), createSnapshot());
         assertNotNull(mCache.getSnapshot(window.getTask().mTaskId, 0 /* userId */,
@@ -60,7 +60,7 @@
     }
 
     @Test
-    public void testAppDied() throws Exception {
+    public void testAppDied() {
         final WindowState window = createWindow(null, FIRST_APPLICATION_WINDOW, "window");
         mCache.putSnapshot(window.getTask(), createSnapshot());
         assertNotNull(mCache.getSnapshot(window.getTask().mTaskId, 0 /* userId */,
@@ -71,7 +71,7 @@
     }
 
     @Test
-    public void testTaskRemoved() throws Exception {
+    public void testTaskRemoved() {
         final WindowState window = createWindow(null, FIRST_APPLICATION_WINDOW, "window");
         mCache.putSnapshot(window.getTask(), createSnapshot());
         assertNotNull(mCache.getSnapshot(window.getTask().mTaskId, 0 /* userId */,
@@ -82,32 +82,32 @@
     }
 
     @Test
-    public void testReduced_notCached() throws Exception {
+    public void testReduced_notCached() {
         final WindowState window = createWindow(null, FIRST_APPLICATION_WINDOW, "window");
-        mPersister.persistSnapshot(window.getTask().mTaskId, sWm.mCurrentUserId, createSnapshot());
+        mPersister.persistSnapshot(window.getTask().mTaskId, mWm.mCurrentUserId, createSnapshot());
         mPersister.waitForQueueEmpty();
-        assertNull(mCache.getSnapshot(window.getTask().mTaskId, sWm.mCurrentUserId,
+        assertNull(mCache.getSnapshot(window.getTask().mTaskId, mWm.mCurrentUserId,
                 false /* restoreFromDisk */, false /* reducedResolution */));
 
         // Load it from disk
-        assertNotNull(mCache.getSnapshot(window.getTask().mTaskId, sWm.mCurrentUserId,
+        assertNotNull(mCache.getSnapshot(window.getTask().mTaskId, mWm.mCurrentUserId,
                 true /* restoreFromDisk */, true /* reducedResolution */));
 
         // Make sure it's not in the cache now.
-        assertNull(mCache.getSnapshot(window.getTask().mTaskId, sWm.mCurrentUserId,
+        assertNull(mCache.getSnapshot(window.getTask().mTaskId, mWm.mCurrentUserId,
                 false /* restoreFromDisk */, false /* reducedResolution */));
     }
 
     @Test
-    public void testRestoreFromDisk() throws Exception {
+    public void testRestoreFromDisk() {
         final WindowState window = createWindow(null, FIRST_APPLICATION_WINDOW, "window");
-        mPersister.persistSnapshot(window.getTask().mTaskId, sWm.mCurrentUserId, createSnapshot());
+        mPersister.persistSnapshot(window.getTask().mTaskId, mWm.mCurrentUserId, createSnapshot());
         mPersister.waitForQueueEmpty();
-        assertNull(mCache.getSnapshot(window.getTask().mTaskId, sWm.mCurrentUserId,
+        assertNull(mCache.getSnapshot(window.getTask().mTaskId, mWm.mCurrentUserId,
                 false /* restoreFromDisk */, false /* reducedResolution */));
 
         // Load it from disk
-        assertNotNull(mCache.getSnapshot(window.getTask().mTaskId, sWm.mCurrentUserId,
+        assertNotNull(mCache.getSnapshot(window.getTask().mTaskId, mWm.mCurrentUserId,
                 true /* restoreFromDisk */, false /* reducedResolution */));
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotControllerTest.java b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotControllerTest.java
index efce063..d2c0765 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotControllerTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotControllerTest.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -20,7 +20,8 @@
 import static android.view.WindowManager.LayoutParams.FLAG_SECURE;
 import static android.view.WindowManager.TRANSIT_UNSET;
 
-import static com.android.server.wm.TaskSnapshotController.*;
+import static com.android.server.wm.TaskSnapshotController.SNAPSHOT_MODE_APP_THEME;
+import static com.android.server.wm.TaskSnapshotController.SNAPSHOT_MODE_REAL;
 
 import static junit.framework.Assert.assertEquals;
 
@@ -28,25 +29,23 @@
 import android.util.ArraySet;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.google.android.collect.Sets;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Test class for {@link TaskSnapshotController}.
  *
- * runtest frameworks-services -c com.android.server.wm.TaskSnapshotControllerTest
+ * Build/Install/Run:
+ *  *  atest FrameworksServicesTests:TaskSnapshotControllerTest
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class TaskSnapshotControllerTest extends WindowTestsBase {
 
     @Test
-    public void testGetClosingApps_closing() throws Exception {
+    public void testGetClosingApps_closing() {
         final WindowState closingWindow = createWindow(null, FIRST_APPLICATION_WINDOW,
                 "closingWindow");
         closingWindow.mAppToken.setVisibility(null, false /* visible */, TRANSIT_UNSET,
@@ -54,13 +53,13 @@
         final ArraySet<AppWindowToken> closingApps = new ArraySet<>();
         closingApps.add(closingWindow.mAppToken);
         final ArraySet<Task> closingTasks = new ArraySet<>();
-        sWm.mTaskSnapshotController.getClosingTasks(closingApps, closingTasks);
+        mWm.mTaskSnapshotController.getClosingTasks(closingApps, closingTasks);
         assertEquals(1, closingTasks.size());
         assertEquals(closingWindow.mAppToken.getTask(), closingTasks.valueAt(0));
     }
 
     @Test
-    public void testGetClosingApps_notClosing() throws Exception {
+    public void testGetClosingApps_notClosing() {
         final WindowState closingWindow = createWindow(null, FIRST_APPLICATION_WINDOW,
                 "closingWindow");
         final WindowState openingWindow = createAppWindow(closingWindow.getTask(),
@@ -72,12 +71,12 @@
         final ArraySet<AppWindowToken> closingApps = new ArraySet<>();
         closingApps.add(closingWindow.mAppToken);
         final ArraySet<Task> closingTasks = new ArraySet<>();
-        sWm.mTaskSnapshotController.getClosingTasks(closingApps, closingTasks);
+        mWm.mTaskSnapshotController.getClosingTasks(closingApps, closingTasks);
         assertEquals(0, closingTasks.size());
     }
 
     @Test
-    public void testGetClosingApps_skipClosingAppsSnapshotTasks() throws Exception {
+    public void testGetClosingApps_skipClosingAppsSnapshotTasks() {
         final WindowState closingWindow = createWindow(null, FIRST_APPLICATION_WINDOW,
                 "closingWindow");
         closingWindow.mAppToken.setVisibility(null, false /* visible */, TRANSIT_UNSET,
@@ -85,29 +84,29 @@
         final ArraySet<AppWindowToken> closingApps = new ArraySet<>();
         closingApps.add(closingWindow.mAppToken);
         final ArraySet<Task> closingTasks = new ArraySet<>();
-        sWm.mTaskSnapshotController.addSkipClosingAppSnapshotTasks(
+        mWm.mTaskSnapshotController.addSkipClosingAppSnapshotTasks(
                 Sets.newArraySet(closingWindow.mAppToken.getTask()));
-        sWm.mTaskSnapshotController.getClosingTasks(closingApps, closingTasks);
+        mWm.mTaskSnapshotController.getClosingTasks(closingApps, closingTasks);
         assertEquals(0, closingTasks.size());
     }
 
     @Test
-    public void testGetSnapshotMode() throws Exception {
+    public void testGetSnapshotMode() {
         final WindowState disabledWindow = createWindow(null,
                 FIRST_APPLICATION_WINDOW, mDisplayContent, "disabledWindow");
         disabledWindow.mAppToken.setDisablePreviewScreenshots(true);
         assertEquals(SNAPSHOT_MODE_APP_THEME,
-                sWm.mTaskSnapshotController.getSnapshotMode(disabledWindow.getTask()));
+                mWm.mTaskSnapshotController.getSnapshotMode(disabledWindow.getTask()));
 
         final WindowState normalWindow = createWindow(null,
                 FIRST_APPLICATION_WINDOW, mDisplayContent, "normalWindow");
         assertEquals(SNAPSHOT_MODE_REAL,
-                sWm.mTaskSnapshotController.getSnapshotMode(normalWindow.getTask()));
+                mWm.mTaskSnapshotController.getSnapshotMode(normalWindow.getTask()));
 
         final WindowState secureWindow = createWindow(null,
                 FIRST_APPLICATION_WINDOW, mDisplayContent, "secureWindow");
         secureWindow.mAttrs.flags |= FLAG_SECURE;
         assertEquals(SNAPSHOT_MODE_APP_THEME,
-                sWm.mTaskSnapshotController.getSnapshotMode(secureWindow.getTask()));
+                mWm.mTaskSnapshotController.getSnapshotMode(secureWindow.getTask()));
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotPersisterLoaderTest.java b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotPersisterLoaderTest.java
index 600b2e5..b0eafee 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotPersisterLoaderTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotPersisterLoaderTest.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -34,23 +34,22 @@
 import android.view.View;
 
 import androidx.test.filters.MediumTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.wm.TaskSnapshotPersister.RemoveObsoleteFilesQueueItem;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 import java.io.File;
+import java.util.function.Predicate;
 
 /**
  * Test class for {@link TaskSnapshotPersister} and {@link TaskSnapshotLoader}
  *
- * atest FrameworksServicesTests:TaskSnapshotPersisterLoaderTest
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:TaskSnapshotPersisterLoaderTest
  */
 @MediumTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class TaskSnapshotPersisterLoaderTest extends TaskSnapshotPersisterTestBase {
 
     private static final Rect TEST_INSETS = new Rect(10, 20, 30, 40);
@@ -59,9 +58,9 @@
     public void testPersistAndLoadSnapshot() {
         mPersister.persistSnapshot(1 , mTestUserId, createSnapshot());
         mPersister.waitForQueueEmpty();
-        final File[] files = new File[] { new File(sFilesDir.getPath() + "/snapshots/1.proto"),
-                new File(sFilesDir.getPath() + "/snapshots/1.jpg"),
-                new File(sFilesDir.getPath() + "/snapshots/1_reduced.jpg")};
+        final File[] files = new File[] { new File(FILES_DIR.getPath() + "/snapshots/1.proto"),
+                new File(FILES_DIR.getPath() + "/snapshots/1.jpg"),
+                new File(FILES_DIR.getPath() + "/snapshots/1_reduced.jpg")};
         assertTrueForFiles(files, File::exists, " must exist");
         final TaskSnapshot snapshot = mLoader.loadTask(1, mTestUserId, false /* reduced */);
         assertNotNull(snapshot);
@@ -70,9 +69,10 @@
         assertEquals(Configuration.ORIENTATION_PORTRAIT, snapshot.getOrientation());
     }
 
-    private void assertTrueForFiles(File[] files, Predicate<File> predicate, String message) {
+    private static void assertTrueForFiles(File[] files, Predicate<File> predicate,
+            String message) {
         for (File file : files) {
-            assertTrue(file.getName() + message, predicate.apply(file));
+            assertTrue(file.getName() + message, predicate.test(file));
         }
     }
 
@@ -81,9 +81,9 @@
         mPersister.persistSnapshot(1, mTestUserId, createSnapshot());
         mPersister.onTaskRemovedFromRecents(1, mTestUserId);
         mPersister.waitForQueueEmpty();
-        assertFalse(new File(sFilesDir.getPath() + "/snapshots/1.proto").exists());
-        assertFalse(new File(sFilesDir.getPath() + "/snapshots/1.jpg").exists());
-        assertFalse(new File(sFilesDir.getPath() + "/snapshots/1_reduced.jpg").exists());
+        assertFalse(new File(FILES_DIR.getPath() + "/snapshots/1.proto").exists());
+        assertFalse(new File(FILES_DIR.getPath() + "/snapshots/1.jpg").exists());
+        assertFalse(new File(FILES_DIR.getPath() + "/snapshots/1_reduced.jpg").exists());
     }
 
     /**
@@ -120,12 +120,12 @@
 
         // Make sure 1,2 were purged but removeObsoleteFiles wasn't.
         final File[] existsFiles = new File[] {
-                new File(sFilesDir.getPath() + "/snapshots/3.proto"),
-                new File(sFilesDir.getPath() + "/snapshots/4.proto")};
+                new File(FILES_DIR.getPath() + "/snapshots/3.proto"),
+                new File(FILES_DIR.getPath() + "/snapshots/4.proto")};
         final File[] nonExistsFiles = new File[] {
-                new File(sFilesDir.getPath() + "/snapshots/100.proto"),
-                new File(sFilesDir.getPath() + "/snapshots/1.proto"),
-                new File(sFilesDir.getPath() + "/snapshots/1.proto")};
+                new File(FILES_DIR.getPath() + "/snapshots/100.proto"),
+                new File(FILES_DIR.getPath() + "/snapshots/1.proto"),
+                new File(FILES_DIR.getPath() + "/snapshots/1.proto")};
         assertTrueForFiles(existsFiles, File::exists, " must exist");
         assertTrueForFiles(nonExistsFiles, file -> !file.exists(), " must not exist");
     }
@@ -149,10 +149,10 @@
         assertTrue(a.isReducedResolution());
         mPersister.persistSnapshot(1 , mTestUserId, a);
         mPersister.waitForQueueEmpty();
-        final File[] files = new File[] { new File(sFilesDir.getPath() + "/snapshots/1.proto"),
-                new File(sFilesDir.getPath() + "/snapshots/1_reduced.jpg")};
+        final File[] files = new File[] { new File(FILES_DIR.getPath() + "/snapshots/1.proto"),
+                new File(FILES_DIR.getPath() + "/snapshots/1_reduced.jpg")};
         final File[] nonExistsFiles = new File[] {
-                new File(sFilesDir.getPath() + "/snapshots/1.jpg"),
+                new File(FILES_DIR.getPath() + "/snapshots/1.jpg"),
         };
         assertTrueForFiles(files, File::exists, " must exist");
         assertTrueForFiles(nonExistsFiles, file -> !file.exists(), " must not exist");
@@ -195,8 +195,8 @@
         TaskSnapshot b = new TaskSnapshotBuilder()
                 .setWindowingMode(WINDOWING_MODE_PINNED)
                 .build();
-        assertTrue(a.getWindowingMode() == WINDOWING_MODE_FULLSCREEN);
-        assertTrue(b.getWindowingMode() == WINDOWING_MODE_PINNED);
+        assertEquals(WINDOWING_MODE_FULLSCREEN, a.getWindowingMode());
+        assertEquals(WINDOWING_MODE_PINNED, b.getWindowingMode());
         mPersister.persistSnapshot(1, mTestUserId, a);
         mPersister.persistSnapshot(2, mTestUserId, b);
         mPersister.waitForQueueEmpty();
@@ -204,8 +204,8 @@
         final TaskSnapshot snapshotB = mLoader.loadTask(2, mTestUserId, false /* reduced */);
         assertNotNull(snapshotA);
         assertNotNull(snapshotB);
-        assertTrue(snapshotA.getWindowingMode() == WINDOWING_MODE_FULLSCREEN);
-        assertTrue(snapshotB.getWindowingMode() == WINDOWING_MODE_PINNED);
+        assertEquals(WINDOWING_MODE_FULLSCREEN, snapshotA.getWindowingMode());
+        assertEquals(WINDOWING_MODE_PINNED, snapshotB.getWindowingMode());
     }
 
     @Test
@@ -239,8 +239,8 @@
         TaskSnapshot b = new TaskSnapshotBuilder()
                 .setSystemUiVisibility(lightBarFlags)
                 .build();
-        assertTrue(a.getSystemUiVisibility() == 0);
-        assertTrue(b.getSystemUiVisibility() == lightBarFlags);
+        assertEquals(0, a.getSystemUiVisibility());
+        assertEquals(lightBarFlags, b.getSystemUiVisibility());
         mPersister.persistSnapshot(1, mTestUserId, a);
         mPersister.persistSnapshot(2, mTestUserId, b);
         mPersister.waitForQueueEmpty();
@@ -248,8 +248,8 @@
         final TaskSnapshot snapshotB = mLoader.loadTask(2, mTestUserId, false /* reduced */);
         assertNotNull(snapshotA);
         assertNotNull(snapshotB);
-        assertTrue(snapshotA.getSystemUiVisibility() == 0);
-        assertTrue(snapshotB.getSystemUiVisibility() == lightBarFlags);
+        assertEquals(0, snapshotA.getSystemUiVisibility());
+        assertEquals(lightBarFlags, snapshotB.getSystemUiVisibility());
     }
 
     @Test
@@ -261,13 +261,13 @@
         mPersister.removeObsoleteFiles(taskIds, new int[] { mTestUserId });
         mPersister.waitForQueueEmpty();
         final File[] existsFiles = new File[] {
-                new File(sFilesDir.getPath() + "/snapshots/1.proto"),
-                new File(sFilesDir.getPath() + "/snapshots/1.jpg"),
-                new File(sFilesDir.getPath() + "/snapshots/1_reduced.jpg") };
+                new File(FILES_DIR.getPath() + "/snapshots/1.proto"),
+                new File(FILES_DIR.getPath() + "/snapshots/1.jpg"),
+                new File(FILES_DIR.getPath() + "/snapshots/1_reduced.jpg") };
         final File[] nonExistsFiles = new File[] {
-                new File(sFilesDir.getPath() + "/snapshots/2.proto"),
-                new File(sFilesDir.getPath() + "/snapshots/2.jpg"),
-                new File(sFilesDir.getPath() + "/snapshots/2_reduced.jpg")};
+                new File(FILES_DIR.getPath() + "/snapshots/2.proto"),
+                new File(FILES_DIR.getPath() + "/snapshots/2.jpg"),
+                new File(FILES_DIR.getPath() + "/snapshots/2_reduced.jpg")};
         assertTrueForFiles(existsFiles, File::exists, " must exist");
         assertTrueForFiles(nonExistsFiles, file -> !file.exists(), " must not exist");
     }
@@ -281,24 +281,12 @@
         mPersister.persistSnapshot(2, mTestUserId, createSnapshot());
         mPersister.waitForQueueEmpty();
         final File[] existsFiles = new File[] {
-                new File(sFilesDir.getPath() + "/snapshots/1.proto"),
-                new File(sFilesDir.getPath() + "/snapshots/1.jpg"),
-                new File(sFilesDir.getPath() + "/snapshots/1_reduced.jpg"),
-                new File(sFilesDir.getPath() + "/snapshots/2.proto"),
-                new File(sFilesDir.getPath() + "/snapshots/2.jpg"),
-                new File(sFilesDir.getPath() + "/snapshots/2_reduced.jpg")};
+                new File(FILES_DIR.getPath() + "/snapshots/1.proto"),
+                new File(FILES_DIR.getPath() + "/snapshots/1.jpg"),
+                new File(FILES_DIR.getPath() + "/snapshots/1_reduced.jpg"),
+                new File(FILES_DIR.getPath() + "/snapshots/2.proto"),
+                new File(FILES_DIR.getPath() + "/snapshots/2.jpg"),
+                new File(FILES_DIR.getPath() + "/snapshots/2_reduced.jpg")};
         assertTrueForFiles(existsFiles, File::exists, " must exist");
     }
-
-    /**
-     * Private predicate definition.
-     *
-     * This is needed because com.android.internal.util.Predicate is deprecated
-     * and can only be used with classes fron android.test.runner. This cannot
-     * use java.util.function.Predicate because that is not present on all API
-     * versions that this test must run on.
-     */
-    private interface Predicate<T> {
-        boolean apply(T t);
-    }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotPersisterTestBase.java b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotPersisterTestBase.java
index 33b137e..0f9b825 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotPersisterTestBase.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotPersisterTestBase.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -21,6 +21,8 @@
 import static android.graphics.GraphicBuffer.USAGE_HW_TEXTURE;
 import static android.graphics.GraphicBuffer.USAGE_SW_READ_RARELY;
 
+import static androidx.test.platform.app.InstrumentationRegistry.getInstrumentation;
+
 import android.app.ActivityManager.TaskSnapshot;
 import android.graphics.Canvas;
 import android.graphics.Color;
@@ -31,51 +33,37 @@
 
 import org.junit.After;
 import org.junit.Before;
-import org.junit.BeforeClass;
 
 import java.io.File;
 
-import androidx.test.InstrumentationRegistry;
-
 /**
  * Base class for tests that use a {@link TaskSnapshotPersister}.
  */
 class TaskSnapshotPersisterTestBase extends WindowTestsBase {
 
     private static final Rect TEST_INSETS = new Rect(10, 20, 30, 40);
+    static final File FILES_DIR = getInstrumentation().getTargetContext().getFilesDir();
 
     TaskSnapshotPersister mPersister;
     TaskSnapshotLoader mLoader;
     int mTestUserId;
-    static File sFilesDir;
 
-    @BeforeClass
-    public static void setUpUser() {
-        sFilesDir = InstrumentationRegistry.getContext().getFilesDir();
-    }
-
-    @Override
     @Before
-    public void setUp() throws Exception {
-        super.setUp();
-
-        final UserManager um = UserManager.get(InstrumentationRegistry.getContext());
+    public void setUp() {
+        final UserManager um = UserManager.get(getInstrumentation().getTargetContext());
         mTestUserId = um.getUserHandle();
-        mPersister = new TaskSnapshotPersister(userId -> sFilesDir);
+        mPersister = new TaskSnapshotPersister(userId -> FILES_DIR);
         mLoader = new TaskSnapshotLoader(mPersister);
         mPersister.start();
     }
 
-    @Override
     @After
-    public void tearDown() throws Exception {
+    public void tearDown() {
         cleanDirectory();
-
-        super.tearDown();
     }
 
     private void cleanDirectory() {
-        final File[] files = new File(sFilesDir, "snapshots").listFiles();
+        final File[] files = new File(FILES_DIR, "snapshots").listFiles();
         if (files == null) {
             return;
         }
@@ -99,7 +87,7 @@
     /**
      * Builds a TaskSnapshot.
      */
-    class TaskSnapshotBuilder {
+    static class TaskSnapshotBuilder {
 
         private float mScale = 1f;
         private boolean mIsRealSnapshot = true;
@@ -107,32 +95,32 @@
         private int mWindowingMode = WINDOWING_MODE_FULLSCREEN;
         private int mSystemUiVisibility = 0;
 
-        public TaskSnapshotBuilder setScale(float scale) {
+        TaskSnapshotBuilder setScale(float scale) {
             mScale = scale;
             return this;
         }
 
-        public TaskSnapshotBuilder setIsRealSnapshot(boolean isRealSnapshot) {
+        TaskSnapshotBuilder setIsRealSnapshot(boolean isRealSnapshot) {
             mIsRealSnapshot = isRealSnapshot;
             return this;
         }
 
-        public TaskSnapshotBuilder setIsTranslucent(boolean isTranslucent) {
+        TaskSnapshotBuilder setIsTranslucent(boolean isTranslucent) {
             mIsTranslucent = isTranslucent;
             return this;
         }
 
-        public TaskSnapshotBuilder setWindowingMode(int windowingMode) {
+        TaskSnapshotBuilder setWindowingMode(int windowingMode) {
             mWindowingMode = windowingMode;
             return this;
         }
 
-        public TaskSnapshotBuilder setSystemUiVisibility(int systemUiVisibility) {
+        TaskSnapshotBuilder setSystemUiVisibility(int systemUiVisibility) {
             mSystemUiVisibility = systemUiVisibility;
             return this;
         }
 
-        public TaskSnapshot build() {
+        TaskSnapshot build() {
             final GraphicBuffer buffer = GraphicBuffer.create(100, 100, PixelFormat.RGBA_8888,
                     USAGE_HW_TEXTURE | USAGE_SW_READ_RARELY | USAGE_SW_READ_RARELY);
             Canvas c = buffer.lockCanvas();
@@ -142,6 +130,5 @@
                     mScale < 1f /* reducedResolution */, mScale, mIsRealSnapshot, mWindowingMode,
                     mSystemUiVisibility, mIsTranslucent);
         }
-
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotSurfaceTest.java b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotSurfaceTest.java
index 91074b9..7c16191 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotSurfaceTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotSurfaceTest.java
@@ -39,21 +39,19 @@
 import android.view.Surface;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.wm.TaskSnapshotSurface.Window;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Test class for {@link TaskSnapshotSurface}.
  *
- * runtest frameworks-services -c com.android.server.wm.TaskSnapshotSurfaceTest
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:TaskSnapshotSurfaceTest
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class TaskSnapshotSurfaceTest extends WindowTestsBase {
 
     private TaskSnapshotSurface mSurface;
@@ -65,7 +63,7 @@
         final TaskSnapshot snapshot = new TaskSnapshot(buffer,
                 ORIENTATION_PORTRAIT, contentInsets, false, 1.0f, true /* isRealSnapshot */,
                 WINDOWING_MODE_FULLSCREEN, 0 /* systemUiVisibility */, false /* isTranslucent */);
-        mSurface = new TaskSnapshotSurface(sWm, new Window(), new Surface(), snapshot, "Test",
+        mSurface = new TaskSnapshotSurface(mWm, new Window(), new Surface(), snapshot, "Test",
                 Color.WHITE, Color.RED, Color.BLUE, sysuiVis, windowFlags, 0, taskBounds,
                 ORIENTATION_PORTRAIT);
     }
@@ -76,7 +74,7 @@
     }
 
     @Test
-    public void fillEmptyBackground_fillHorizontally() throws Exception {
+    public void fillEmptyBackground_fillHorizontally() {
         setupSurface(200, 100);
         final Canvas mockCanvas = mock(Canvas.class);
         when(mockCanvas.getWidth()).thenReturn(200);
@@ -86,7 +84,7 @@
     }
 
     @Test
-    public void fillEmptyBackground_fillVertically() throws Exception {
+    public void fillEmptyBackground_fillVertically() {
         setupSurface(100, 200);
         final Canvas mockCanvas = mock(Canvas.class);
         when(mockCanvas.getWidth()).thenReturn(100);
@@ -96,7 +94,7 @@
     }
 
     @Test
-    public void fillEmptyBackground_fillBoth() throws Exception {
+    public void fillEmptyBackground_fillBoth() {
         setupSurface(200, 200);
         final Canvas mockCanvas = mock(Canvas.class);
         when(mockCanvas.getWidth()).thenReturn(200);
@@ -107,7 +105,7 @@
     }
 
     @Test
-    public void fillEmptyBackground_dontFill_sameSize() throws Exception {
+    public void fillEmptyBackground_dontFill_sameSize() {
         setupSurface(100, 100);
         final Canvas mockCanvas = mock(Canvas.class);
         when(mockCanvas.getWidth()).thenReturn(100);
@@ -117,7 +115,7 @@
     }
 
     @Test
-    public void fillEmptyBackground_dontFill_bitmapLarger() throws Exception {
+    public void fillEmptyBackground_dontFill_bitmapLarger() {
         setupSurface(100, 100);
         final Canvas mockCanvas = mock(Canvas.class);
         when(mockCanvas.getWidth()).thenReturn(100);
diff --git a/services/tests/servicestests/src/com/android/server/wm/TaskStackContainersTests.java b/services/tests/servicestests/src/com/android/server/wm/TaskStackContainersTests.java
index 0e9a63c..f01e9f0 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskStackContainersTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskStackContainersTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -27,17 +27,17 @@
 
 import android.platform.test.annotations.Presubmit;
 
+import androidx.test.filters.SmallTest;
+
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 
-import androidx.test.filters.SmallTest;
-
 /**
  * Tests for the {@link DisplayContent.TaskStackContainers} container in {@link DisplayContent}.
  *
  * Build/Install/Run:
- *  atest FrameworksServicesTests:com.android.server.wm.TaskStackContainersTests
+ *  atest FrameworksServicesTests:TaskStackContainersTests
  */
 @SmallTest
 @Presubmit
@@ -45,11 +45,8 @@
 
     private TaskStack mPinnedStack;
 
-    @Override
     @Before
     public void setUp() throws Exception {
-        super.setUp();
-
         mPinnedStack = createStackControllerOnStackOnDisplay(
                 WINDOWING_MODE_PINNED, ACTIVITY_TYPE_STANDARD, mDisplayContent).mContainer;
         // Stack should contain visible app window to be considered visible.
@@ -61,12 +58,9 @@
         assertTrue(mPinnedStack.isVisible());
     }
 
-    @Override
     @After
     public void tearDown() throws Exception {
         mPinnedStack.removeImmediately();
-
-        super.tearDown();
     }
 
     @Test
@@ -121,14 +115,14 @@
         final Task task = createTaskInStack(stack, 0 /* userId */);
 
         // Add another display at top.
-        sWm.mRoot.positionChildAt(WindowContainer.POSITION_TOP, createNewDisplay(),
+        mWm.mRoot.positionChildAt(WindowContainer.POSITION_TOP, createNewDisplay(),
                 false /* includingParents */);
 
         // Move the task of {@code mDisplayContent} to top.
         stack.positionChildAt(WindowContainer.POSITION_TOP, task, true /* includingParents */);
-        final int indexOfDisplayWithPinnedStack = sWm.mRoot.mChildren.indexOf(mDisplayContent);
+        final int indexOfDisplayWithPinnedStack = mWm.mRoot.mChildren.indexOf(mDisplayContent);
 
         assertEquals("The testing DisplayContent should be moved to top with task",
-                sWm.mRoot.getChildCount() - 1, indexOfDisplayWithPinnedStack);
+                mWm.mRoot.getChildCount() - 1, indexOfDisplayWithPinnedStack);
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/TaskStackTests.java b/services/tests/servicestests/src/com/android/server/wm/TaskStackTests.java
index cb5c1cd..7ac3318 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskStackTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskStackTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -25,24 +25,21 @@
 import android.platform.test.annotations.Presubmit;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Tests for the {@link TaskStack} class.
  *
  * Build/Install/Run:
- *  bit FrameworksServicesTests:com.android.server.wm.TaskStackTests
+ *  atest FrameworksServicesTests:TaskStackTests
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class TaskStackTests extends WindowTestsBase {
 
     @Test
-    public void testStackPositionChildAt() throws Exception {
+    public void testStackPositionChildAt() {
         final TaskStack stack = createTaskStackOnDisplay(mDisplayContent);
         final Task task1 = createTaskInStack(stack, 0 /* userId */);
         final Task task2 = createTaskInStack(stack, 1 /* userId */);
@@ -59,7 +56,7 @@
     }
 
     @Test
-    public void testClosingAppDifferentStackOrientation() throws Exception {
+    public void testClosingAppDifferentStackOrientation() {
         final TaskStack stack = createTaskStackOnDisplay(mDisplayContent);
         final Task task1 = createTaskInStack(stack, 0 /* userId */);
         WindowTestUtils.TestAppWindowToken appWindowToken1 =
@@ -79,7 +76,7 @@
     }
 
     @Test
-    public void testMoveTaskToBackDifferentStackOrientation() throws Exception {
+    public void testMoveTaskToBackDifferentStackOrientation() {
         final TaskStack stack = createTaskStackOnDisplay(mDisplayContent);
         final Task task1 = createTaskInStack(stack, 0 /* userId */);
         WindowTestUtils.TestAppWindowToken appWindowToken1 =
@@ -99,7 +96,7 @@
     }
 
     @Test
-    public void testStackRemoveImmediately() throws Exception {
+    public void testStackRemoveImmediately() {
         final TaskStack stack = createTaskStackOnDisplay(mDisplayContent);
         final Task task = createTaskInStack(stack, 0 /* userId */);
         assertEquals(stack, task.mStack);
diff --git a/services/tests/servicestests/src/com/android/server/wm/TaskWindowContainerControllerTests.java b/services/tests/servicestests/src/com/android/server/wm/TaskWindowContainerControllerTests.java
index edd7664..1af79e4 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskWindowContainerControllerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskWindowContainerControllerTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -24,24 +24,21 @@
 import android.platform.test.annotations.Presubmit;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Test class for {@link TaskWindowContainerController}.
  *
  * Build/Install/Run:
- *  bit FrameworksServicesTests:com.android.server.wm.TaskWindowContainerControllerTests
+ *  atest FrameworksServicesTests:TaskWindowContainerControllerTests
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class TaskWindowContainerControllerTests extends WindowTestsBase {
 
     @Test
-    public void testRemoveContainer() throws Exception {
+    public void testRemoveContainer() {
         final WindowTestUtils.TestTaskWindowContainerController taskController =
                 new WindowTestUtils.TestTaskWindowContainerController(this);
         final WindowTestUtils.TestAppWindowContainerController appController =
@@ -54,7 +51,7 @@
     }
 
     @Test
-    public void testRemoveContainer_deferRemoval() throws Exception {
+    public void testRemoveContainer_deferRemoval() {
         final WindowTestUtils.TestTaskWindowContainerController taskController =
                 new WindowTestUtils.TestTaskWindowContainerController(this);
         final WindowTestUtils.TestAppWindowContainerController appController =
@@ -79,7 +76,7 @@
     }
 
     @Test
-    public void testReparent() throws Exception {
+    public void testReparent() {
         final StackWindowController stackController1 =
                 createStackControllerOnDisplay(mDisplayContent);
         final WindowTestUtils.TestTaskWindowContainerController taskController =
@@ -116,7 +113,7 @@
     }
 
     @Test
-    public void testReparent_BetweenDisplays() throws Exception {
+    public void testReparent_BetweenDisplays() {
         // Create first stack on primary display.
         final StackWindowController stack1Controller =
                 createStackControllerOnDisplay(mDisplayContent);
diff --git a/services/tests/servicestests/src/com/android/server/wm/TestIWindow.java b/services/tests/servicestests/src/com/android/server/wm/TestIWindow.java
index 353aa7d..e8d0a06 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TestIWindow.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TestIWindow.java
@@ -11,13 +11,11 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
 
-import com.android.internal.os.IResultReceiver;
-
 import android.graphics.Rect;
 import android.os.Bundle;
 import android.os.ParcelFileDescriptor;
@@ -27,87 +25,71 @@
 import android.view.DragEvent;
 import android.view.IWindow;
 
+import com.android.internal.os.IResultReceiver;
+
 public class TestIWindow extends IWindow.Stub {
     @Override
     public void executeCommand(String command, String parameters,
-            ParcelFileDescriptor descriptor)
-            throws RemoteException {
-
+            ParcelFileDescriptor descriptor) throws RemoteException {
     }
 
     @Override
     public void resized(Rect frame, Rect overscanInsets, Rect contentInsets, Rect visibleInsets,
             Rect stableInsets, Rect outsets, boolean reportDraw, MergedConfiguration mergedConfig,
             Rect backDropFrame, boolean forceLayout, boolean alwaysConsumeNavBar, int displayId,
-            DisplayCutout.ParcelableWrapper displayCutout)
-            throws RemoteException {
-
+            DisplayCutout.ParcelableWrapper displayCutout) throws RemoteException {
     }
 
     @Override
     public void moved(int newX, int newY) throws RemoteException {
-
     }
 
     @Override
     public void dispatchAppVisibility(boolean visible) throws RemoteException {
-
     }
 
     @Override
     public void dispatchGetNewSurface() throws RemoteException {
-
     }
 
     @Override
-    public void windowFocusChanged(boolean hasFocus, boolean inTouchMode)
-            throws RemoteException {
-
+    public void windowFocusChanged(boolean hasFocus, boolean inTouchMode) throws RemoteException {
     }
 
     @Override
     public void closeSystemDialogs(String reason) throws RemoteException {
-
     }
 
     @Override
-    public void dispatchWallpaperOffsets(float x, float y, float xStep, float yStep,
-            boolean sync)
+    public void dispatchWallpaperOffsets(float x, float y, float xStep, float yStep, boolean sync)
             throws RemoteException {
-
     }
 
     @Override
     public void dispatchWallpaperCommand(String action, int x, int y, int z, Bundle extras,
             boolean sync) throws RemoteException {
-
     }
 
     @Override
     public void dispatchDragEvent(DragEvent event) throws RemoteException {
-
     }
 
     @Override
     public void updatePointerIcon(float x, float y) throws RemoteException {
-
     }
 
     @Override
     public void dispatchSystemUiVisibilityChanged(int seq, int globalVisibility, int localValue,
             int localChanges) throws RemoteException {
-
     }
 
     @Override
     public void dispatchWindowShown() throws RemoteException {
-
     }
 
     @Override
     public void requestAppKeyboardShortcuts(IResultReceiver receiver, int deviceId)
             throws RemoteException {
-
     }
 
     @Override
diff --git a/services/tests/servicestests/src/com/android/server/wm/TestWindowManagerPolicy.java b/services/tests/servicestests/src/com/android/server/wm/TestWindowManagerPolicy.java
index 19abd9e..0165e7d 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TestWindowManagerPolicy.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TestWindowManagerPolicy.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -46,8 +46,6 @@
 import java.util.function.Supplier;
 
 class TestWindowManagerPolicy implements WindowManagerPolicy {
-    private static final String TAG = "TestWindowManagerPolicy";
-
     private final Supplier<WindowManagerService> mWmSupplier;
 
     int rotationToReport = 0;
@@ -55,21 +53,18 @@
 
     private Runnable mRunnableWhenAddingSplashScreen;
 
-    public TestWindowManagerPolicy(Supplier<WindowManagerService> wmSupplier) {
-
+    TestWindowManagerPolicy(Supplier<WindowManagerService> wmSupplier) {
         mWmSupplier = wmSupplier;
     }
 
     @Override
     public void registerShortcutKey(long shortcutCode, IShortcutService shortcutKeyReceiver)
             throws RemoteException {
-
     }
 
     @Override
     public void init(Context context, IWindowManager windowManager,
             WindowManagerFuncs windowManagerFuncs) {
-
     }
 
     public void setDefaultDisplay(DisplayContentInfo displayContentInfo) {
@@ -93,7 +88,6 @@
     @Override
     public void adjustConfigurationLw(Configuration config, int keyboardPresence,
             int navigationPresence) {
-
     }
 
     @Override
@@ -179,7 +173,6 @@
 
     @Override
     public void removeWindowLw(WindowState win) {
-
     }
 
     @Override
@@ -189,7 +182,6 @@
 
     @Override
     public void selectRotationAnimationLw(int[] anim) {
-
     }
 
     @Override
@@ -220,14 +212,12 @@
     }
 
     @Override
-    public long interceptKeyBeforeDispatching(WindowState win, KeyEvent event,
-            int policyFlags) {
+    public long interceptKeyBeforeDispatching(WindowState win, KeyEvent event, int policyFlags) {
         return 0;
     }
 
     @Override
-    public KeyEvent dispatchUnhandledKey(WindowState win, KeyEvent event,
-            int policyFlags) {
+    public KeyEvent dispatchUnhandledKey(WindowState win, KeyEvent event, int policyFlags) {
         return null;
     }
 
@@ -238,12 +228,11 @@
 
     @Override
     public void beginPostLayoutPolicyLw(int displayWidth, int displayHeight) {
-
     }
 
     @Override
-    public void applyPostLayoutPolicyLw(WindowState win,
-            WindowManager.LayoutParams attrs, WindowState attached, WindowState imeTarget) {
+    public void applyPostLayoutPolicyLw(WindowState win, WindowManager.LayoutParams attrs,
+            WindowState attached, WindowState imeTarget) {
     }
 
     @Override
@@ -257,49 +246,40 @@
     }
 
     @Override
-    public int focusChangedLw(WindowState lastFocus,
-            WindowState newFocus) {
+    public int focusChangedLw(WindowState lastFocus, WindowState newFocus) {
         return 0;
     }
 
     @Override
     public void startedWakingUp() {
-
     }
 
     @Override
     public void finishedWakingUp() {
-
     }
 
     @Override
     public void startedGoingToSleep(int why) {
-
     }
 
     @Override
     public void finishedGoingToSleep(int why) {
-
     }
 
     @Override
     public void screenTurningOn(ScreenOnListener screenOnListener) {
-
     }
 
     @Override
     public void screenTurnedOn() {
-
     }
 
     @Override
     public void screenTurningOff(ScreenOffListener screenOffListener) {
-
     }
 
     @Override
     public void screenTurnedOff() {
-
     }
 
     @Override
@@ -314,22 +294,18 @@
 
     @Override
     public void notifyLidSwitchChanged(long whenNanos, boolean lidOpen) {
-
     }
 
     @Override
     public void notifyCameraLensCoverSwitchChanged(long whenNanos, boolean lensCovered) {
-
     }
 
     @Override
     public void enableKeyguard(boolean enabled) {
-
     }
 
     @Override
     public void exitKeyguardSecurely(OnKeyguardExitResult callback) {
-
     }
 
     @Override
@@ -382,53 +358,44 @@
     }
 
     public void setSafeMode(boolean safeMode) {
-
     }
 
     @Override
     public void systemReady() {
-
     }
 
     @Override
     public void systemBooted() {
-
     }
 
     @Override
     public void showBootMessage(CharSequence msg, boolean always) {
-
     }
 
     @Override
     public void hideBootMessages() {
-
     }
 
     @Override
     public void userActivity() {
-
     }
 
     @Override
     public void enableScreenAfterBoot() {
-
     }
 
     @Override
-    public boolean performHapticFeedbackLw(WindowState win, int effectId,
-            boolean always, String reason) {
+    public boolean performHapticFeedbackLw(WindowState win, int effectId, boolean always,
+            String reason) {
         return false;
     }
 
     @Override
     public void keepScreenOnStartedLw() {
-
     }
 
     @Override
     public void keepScreenOnStoppedLw() {
-
     }
 
     @Override
@@ -443,37 +410,30 @@
 
     @Override
     public void lockNow(Bundle options) {
-
     }
 
     @Override
     public void showRecentApps() {
-
     }
 
     @Override
     public void showGlobalActions() {
-
     }
 
     @Override
     public void setCurrentUserLw(int newUserId) {
-
     }
 
     @Override
     public void setSwitchingUser(boolean switching) {
-
     }
 
     @Override
     public void writeToProto(ProtoOutputStream proto, long fieldId) {
-
     }
 
     @Override
     public void dump(String prefix, PrintWriter writer, String[] args) {
-
     }
 
     @Override
@@ -483,13 +443,11 @@
 
     @Override
     public void startKeyguardExitAnimation(long startTime, long fadeoutDuration) {
-
     }
 
     @Override
     public void getStableInsetsLw(int displayRotation, int displayWidth, int displayHeight,
             DisplayCutout cutout, Rect outInsets) {
-
     }
 
     @Override
@@ -506,7 +464,6 @@
     @Override
     public void getNonDecorInsetsLw(int displayRotation, int displayWidth, int displayHeight,
             DisplayCutout cutout, Rect outInsets) {
-
     }
 
     @Override
@@ -517,7 +474,6 @@
 
     @Override
     public void onConfigurationChanged(DisplayContentInfo displayContentInfo) {
-
     }
 
     @Override
@@ -528,12 +484,10 @@
 
     @Override
     public void setPipVisibilityLw(boolean visible) {
-
     }
 
     @Override
     public void setRecentsVisibilityLw(boolean visible) {
-
     }
 
     @Override
diff --git a/services/tests/servicestests/src/com/android/server/wm/UnknownAppVisibilityControllerTest.java b/services/tests/servicestests/src/com/android/server/wm/UnknownAppVisibilityControllerTest.java
index 54456fb..9e22c0a 100644
--- a/services/tests/servicestests/src/com/android/server/wm/UnknownAppVisibilityControllerTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/UnknownAppVisibilityControllerTest.java
@@ -11,52 +11,50 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
 
 import static junit.framework.Assert.assertTrue;
 
+import android.os.SystemClock;
 import android.platform.test.annotations.Presubmit;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Test class for {@link AppTransition}.
  *
- * runtest frameworks-services -c com.android.server.wm.UnknownAppVisibilityControllerTest
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:UnknownAppVisibilityControllerTest
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class UnknownAppVisibilityControllerTest extends WindowTestsBase {
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
         mDisplayContent.mUnknownAppVisibilityController.clear();
     }
 
     @Test
-    public void testFlow() throws Exception {
+    public void testFlow() {
         final AppWindowToken token = WindowTestUtils.createTestAppWindowToken(mDisplayContent);
         mDisplayContent.mUnknownAppVisibilityController.notifyLaunched(token);
         mDisplayContent.mUnknownAppVisibilityController.notifyAppResumedFinished(token);
         mDisplayContent.mUnknownAppVisibilityController.notifyRelayouted(token);
 
         // Make sure our handler processed the message.
-        Thread.sleep(100);
+        SystemClock.sleep(100);
         assertTrue(mDisplayContent.mUnknownAppVisibilityController.allResolved());
     }
 
     @Test
-    public void testMultiple() throws Exception {
+    public void testMultiple() {
         final AppWindowToken token1 = WindowTestUtils.createTestAppWindowToken(mDisplayContent);
         final AppWindowToken token2 = WindowTestUtils.createTestAppWindowToken(mDisplayContent);
         mDisplayContent.mUnknownAppVisibilityController.notifyLaunched(token1);
@@ -67,12 +65,12 @@
         mDisplayContent.mUnknownAppVisibilityController.notifyRelayouted(token2);
 
         // Make sure our handler processed the message.
-        Thread.sleep(100);
+        SystemClock.sleep(100);
         assertTrue(mDisplayContent.mUnknownAppVisibilityController.allResolved());
     }
 
     @Test
-    public void testClear() throws Exception {
+    public void testClear() {
         final AppWindowToken token = WindowTestUtils.createTestAppWindowToken(mDisplayContent);
         mDisplayContent.mUnknownAppVisibilityController.notifyLaunched(token);
         mDisplayContent.mUnknownAppVisibilityController.clear();;
@@ -80,7 +78,7 @@
     }
 
     @Test
-    public void testAppRemoved() throws Exception {
+    public void testAppRemoved() {
         final AppWindowToken token = WindowTestUtils.createTestAppWindowToken(mDisplayContent);
         mDisplayContent.mUnknownAppVisibilityController.notifyLaunched(token);
         mDisplayContent.mUnknownAppVisibilityController.appRemovedOrHidden(token);
diff --git a/services/tests/servicestests/src/com/android/server/wm/WallpaperControllerTests.java b/services/tests/servicestests/src/com/android/server/wm/WallpaperControllerTests.java
index e3280ca..25e73e3 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WallpaperControllerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WallpaperControllerTests.java
@@ -1,3 +1,19 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package com.android.server.wm;
 
 import static android.view.WindowManager.LayoutParams.TYPE_WALLPAPER;
@@ -13,33 +29,30 @@
 import android.platform.test.annotations.Presubmit;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Tests for the {@link WallpaperController} class.
  *
  * Build/Install/Run:
- *  atest com.android.server.wm.WallpaperControllerTests
+ *  atest FrameworksServicesTests:WallpaperControllerTests
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class WallpaperControllerTests extends WindowTestsBase {
     @Test
     public void testWallpaperScreenshot() {
         WindowSurfaceController windowSurfaceController = mock(WindowSurfaceController.class);
 
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             // No wallpaper
             final DisplayContent dc = createNewDisplay();
-            Bitmap wallpaperBitmap = sWm.mRoot.mWallpaperController.screenshotWallpaperLocked();
+            Bitmap wallpaperBitmap = mWm.mRoot.mWallpaperController.screenshotWallpaperLocked();
             assertNull(wallpaperBitmap);
 
             // No wallpaper WSA Surface
-            WindowToken wallpaperWindowToken = new WallpaperWindowToken(sWm, mock(IBinder.class),
+            WindowToken wallpaperWindowToken = new WallpaperWindowToken(mWm, mock(IBinder.class),
                     true, dc, true /* ownerCanManageAppTokens */);
             WindowState wallpaperWindow = createWindow(null /* parent */, TYPE_WALLPAPER,
                     wallpaperWindowToken, "wallpaperWindow");
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowConfigurationTests.java b/services/tests/servicestests/src/com/android/server/wm/WindowConfigurationTests.java
index e7cc285..4369c96 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowConfigurationTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowConfigurationTests.java
@@ -36,26 +36,24 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
+import org.junit.Before;
 import org.junit.Test;
 
 /**
  * Test class to for {@link android.app.WindowConfiguration}.
  *
  * Build/Install/Run:
- *  bit FrameworksServicesTests:com.android.server.wm.WindowConfigurationTests
+ *  atest FrameworksServicesTests:WindowConfigurationTests
  */
-@SmallTest
 @FlakyTest(bugId = 74078662)
+@SmallTest
 @Presubmit
-@org.junit.runner.RunWith(AndroidJUnit4.class)
 public class WindowConfigurationTests extends WindowTestsBase {
     private Rect mParentBounds;
 
-    @Override
+    @Before
     public void setUp() throws Exception {
-        super.setUp();
         mParentBounds = new Rect(10 /*left*/, 30 /*top*/, 80 /*right*/, 60 /*bottom*/);
     }
 
@@ -95,7 +93,7 @@
 
     /** Tests {@link android.app.WindowConfiguration#compareTo(WindowConfiguration)}. */
     @Test
-    public void testConfigurationCompareTo() throws Exception {
+    public void testConfigurationCompareTo() {
         final Configuration blankConfig = new Configuration();
         final WindowConfiguration blankWinConfig = new WindowConfiguration();
 
@@ -135,7 +133,7 @@
     }
 
     @Test
-    public void testSetActivityType() throws Exception {
+    public void testSetActivityType() {
         final WindowConfiguration config = new WindowConfiguration();
         config.setActivityType(ACTIVITY_TYPE_HOME);
         assertEquals(ACTIVITY_TYPE_HOME, config.getActivityType());
@@ -147,12 +145,12 @@
 
     /** Ensures the configuration app bounds at the root level match the app dimensions. */
     @Test
-    public void testAppBounds_RootConfigurationBounds() throws Exception {
+    public void testAppBounds_RootConfigurationBounds() {
         final DisplayInfo info = mDisplayContent.getDisplayInfo();
         info.appWidth = 1024;
         info.appHeight = 768;
 
-        final Rect appBounds = sWm.computeNewConfiguration(
+        final Rect appBounds = mWm.computeNewConfiguration(
                 mDisplayContent.getDisplayId()).windowConfiguration.getAppBounds();
         // The bounds should always be positioned in the top left.
         assertEquals(appBounds.left, 0);
@@ -165,7 +163,7 @@
 
     /** Ensures that bounds are clipped to their parent. */
     @Test
-    public void testAppBounds_BoundsClipping() throws Exception {
+    public void testAppBounds_BoundsClipping() {
         final Rect shiftedBounds = new Rect(mParentBounds);
         shiftedBounds.offset(10, 10);
         final Rect expectedBounds = new Rect(mParentBounds);
@@ -176,7 +174,7 @@
 
     /** Ensures that empty bounds are not propagated to the configuration. */
     @Test
-    public void testAppBounds_EmptyBounds() throws Exception {
+    public void testAppBounds_EmptyBounds() {
         final Rect emptyBounds = new Rect();
         testStackBoundsConfiguration(WINDOWING_MODE_FULLSCREEN, mParentBounds, emptyBounds,
                 null /*ExpectedBounds*/);
@@ -184,7 +182,7 @@
 
     /** Ensures that bounds on freeform stacks are not clipped. */
     @Test
-    public void testAppBounds_FreeFormBounds() throws Exception {
+    public void testAppBounds_FreeFormBounds() {
         final Rect freeFormBounds = new Rect(mParentBounds);
         freeFormBounds.offset(10, 10);
         testStackBoundsConfiguration(WINDOWING_MODE_FREEFORM, mParentBounds, freeFormBounds,
@@ -193,7 +191,7 @@
 
     /** Ensures that fully contained bounds are not clipped. */
     @Test
-    public void testAppBounds_ContainedBounds() throws Exception {
+    public void testAppBounds_ContainedBounds() {
         final Rect insetBounds = new Rect(mParentBounds);
         insetBounds.inset(5, 5, 5, 5);
         testStackBoundsConfiguration(
@@ -202,7 +200,7 @@
 
     /** Ensures that full screen free form bounds are clipped */
     @Test
-    public void testAppBounds_FullScreenFreeFormBounds() throws Exception {
+    public void testAppBounds_FullScreenFreeFormBounds() {
         final Rect fullScreenBounds = new Rect(0, 0, mDisplayInfo.logicalWidth,
                 mDisplayInfo.logicalHeight);
         testStackBoundsConfiguration(WINDOWING_MODE_FULLSCREEN, mParentBounds, fullScreenBounds,
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowContainerControllerTests.java b/services/tests/servicestests/src/com/android/server/wm/WindowContainerControllerTests.java
index 6b1feb8..7592f1c 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowContainerControllerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowContainerControllerTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -28,7 +28,6 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Test;
 
@@ -36,18 +35,17 @@
  * Test class for {@link WindowContainerController}.
  *
  * Build/Install/Run:
- *  bit FrameworksServicesTests:com.android.server.wm.WindowContainerControllerTests
+ *  atest FrameworksServicesTests:WindowContainerControllerTests
  */
+@FlakyTest(bugId = 74078662)
 @SmallTest
 @Presubmit
-@FlakyTest(bugId = 74078662)
-@org.junit.runner.RunWith(AndroidJUnit4.class)
 public class WindowContainerControllerTests extends WindowTestsBase {
 
     @Test
-    public void testCreation() throws Exception {
-        final WindowContainerController controller = new WindowContainerController(null, sWm);
-        final WindowContainer container = new WindowContainer(sWm);
+    public void testCreation() {
+        final WindowContainerController controller = new WindowContainerController<>(null, mWm);
+        final WindowContainer container = new WindowContainer(mWm);
 
         container.setController(controller);
         assertEquals(controller, container.getController());
@@ -55,9 +53,9 @@
     }
 
     @Test
-    public void testSetContainer() throws Exception {
-        final WindowContainerController controller = new WindowContainerController(null, sWm);
-        final WindowContainer container = new WindowContainer(sWm);
+    public void testSetContainer() {
+        final WindowContainerController controller = new WindowContainerController<>(null, mWm);
+        final WindowContainer container = new WindowContainer(mWm);
 
         controller.setContainer(container);
         assertEquals(controller.mContainer, container);
@@ -65,7 +63,7 @@
         // Assert we can't change the container to another one once set
         boolean gotException = false;
         try {
-            controller.setContainer(new WindowContainer(sWm));
+            controller.setContainer(new WindowContainer(mWm));
         } catch (IllegalArgumentException e) {
             gotException = true;
         }
@@ -77,9 +75,9 @@
     }
 
     @Test
-    public void testRemoveContainer() throws Exception {
-        final WindowContainerController controller = new WindowContainerController(null, sWm);
-        final WindowContainer container = new WindowContainer(sWm);
+    public void testRemoveContainer() {
+        final WindowContainerController controller = new WindowContainerController<>(null, mWm);
+        final WindowContainer container = new WindowContainer(mWm);
 
         controller.setContainer(container);
         assertEquals(controller.mContainer, container);
@@ -89,9 +87,9 @@
     }
 
     @Test
-    public void testOnOverrideConfigurationChanged() throws Exception {
-        final WindowContainerController controller = new WindowContainerController(null, sWm);
-        final WindowContainer container = new WindowContainer(sWm);
+    public void testOnOverrideConfigurationChanged() {
+        final WindowContainerController controller = new WindowContainerController<>(null, mWm);
+        final WindowContainer container = new WindowContainer(mWm);
 
         controller.setContainer(container);
         assertEquals(controller.mContainer, container);
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowContainerTests.java b/services/tests/servicestests/src/com/android/server/wm/WindowContainerTests.java
index dc763b9..e59afd6 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowContainerTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowContainerTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -46,10 +46,8 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 import java.util.Comparator;
 
@@ -57,24 +55,23 @@
  * Test class for {@link WindowContainer}.
  *
  * Build/Install/Run:
- *  atest FrameworksServicesTests:com.android.server.wm.WindowContainerTests
+ *  atest FrameworksServicesTests:WindowContainerTests
  */
 @SmallTest
 @Presubmit
 @FlakyTest(bugId = 74078662)
-@RunWith(AndroidJUnit4.class)
 public class WindowContainerTests extends WindowTestsBase {
 
     @Test
-    public void testCreation() throws Exception {
-        final TestWindowContainer w = new TestWindowContainerBuilder().setLayer(0).build();
+    public void testCreation() {
+        final TestWindowContainer w = new TestWindowContainerBuilder(mWm).setLayer(0).build();
         assertNull("window must have no parent", w.getParentWindow());
         assertEquals("window must have no children", 0, w.getChildrenCount());
     }
 
     @Test
-    public void testAdd() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testAdd() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer layer1 = root.addChildWindow(builder.setLayer(1));
@@ -113,23 +110,24 @@
     }
 
     @Test
-    public void testAddChildSetsSurfacePosition() throws Exception {
-        MockSurfaceBuildingContainer top = new MockSurfaceBuildingContainer();
+    public void testAddChildSetsSurfacePosition() {
+        try (MockSurfaceBuildingContainer top = new MockSurfaceBuildingContainer(mWm)) {
 
-        final SurfaceControl.Transaction transaction = mock(SurfaceControl.Transaction.class);
-        sWm.mTransactionFactory = () -> transaction;
+            final SurfaceControl.Transaction transaction = mock(SurfaceControl.Transaction.class);
+            mWm.mTransactionFactory = () -> transaction;
 
-        WindowContainer child = new WindowContainer(sWm);
-        child.setBounds(1, 1, 10, 10);
+            WindowContainer child = new WindowContainer(mWm);
+            child.setBounds(1, 1, 10, 10);
 
-        verify(transaction, never()).setPosition(any(), anyFloat(), anyFloat());
-        top.addChild(child, 0);
-        verify(transaction, times(1)).setPosition(any(), eq(1.f), eq(1.f));
+            verify(transaction, never()).setPosition(any(), anyFloat(), anyFloat());
+            top.addChild(child, 0);
+            verify(transaction, times(1)).setPosition(any(), eq(1.f), eq(1.f));
+        }
     }
 
     @Test
-    public void testAdd_AlreadyHasParent() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testAdd_AlreadyHasParent() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer child1 = root.addChildWindow();
@@ -153,8 +151,8 @@
     }
 
     @Test
-    public void testHasChild() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testHasChild() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer child1 = root.addChildWindow();
@@ -183,8 +181,8 @@
     }
 
     @Test
-    public void testRemoveImmediately() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testRemoveImmediately() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer child1 = root.addChildWindow();
@@ -218,9 +216,9 @@
     }
 
     @Test
-    public void testRemoveImmediately_WithController() throws Exception {
-        final WindowContainer container = new WindowContainer(sWm);
-        final WindowContainerController controller = new WindowContainerController(null, sWm);
+    public void testRemoveImmediately_WithController() {
+        final WindowContainer container = new WindowContainer(mWm);
+        final WindowContainerController controller = new WindowContainerController<>(null, mWm);
 
         container.setController(controller);
         assertEquals(controller, container.getController());
@@ -232,9 +230,9 @@
     }
 
     @Test
-    public void testSetController() throws Exception {
-        final WindowContainerController controller = new WindowContainerController(null, sWm);
-        final WindowContainer container = new WindowContainer(sWm);
+    public void testSetController() {
+        final WindowContainerController controller = new WindowContainerController<>(null, mWm);
+        final WindowContainer container = new WindowContainer(mWm);
 
         container.setController(controller);
         assertEquals(controller, container.getController());
@@ -243,7 +241,7 @@
         // Assert we can't change the controller to another one once set
         boolean gotException = false;
         try {
-            container.setController(new WindowContainerController(null, sWm));
+            container.setController(new WindowContainerController<>(null, mWm));
         } catch (IllegalArgumentException e) {
             gotException = true;
         }
@@ -256,8 +254,8 @@
     }
 
     @Test
-    public void testAddChildByIndex() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testAddChildByIndex() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer child = root.addChildWindow();
@@ -283,8 +281,8 @@
     }
 
     @Test
-    public void testPositionChildAt() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testPositionChildAt() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer child1 = root.addChildWindow();
@@ -307,8 +305,8 @@
     }
 
     @Test
-    public void testPositionChildAtIncludeParents() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testPositionChildAtIncludeParents() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer child1 = root.addChildWindow();
@@ -349,12 +347,11 @@
     }
 
     @Test
-    public void testPositionChildAtInvalid() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testPositionChildAtInvalid() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer child1 = root.addChildWindow();
-        final TestWindowContainer child2 = root.addChildWindow();
 
         boolean gotException = false;
         try {
@@ -376,8 +373,8 @@
     }
 
     @Test
-    public void testIsAnimating() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testIsAnimating() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer child1 = root.addChildWindow(builder.setIsAnimating(true));
@@ -402,8 +399,8 @@
     }
 
     @Test
-    public void testIsVisible() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testIsVisible() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer child1 = root.addChildWindow(builder.setIsVisible(true));
@@ -422,7 +419,7 @@
 
     @Test
     public void testOverrideConfigurationAncestorNotification() {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer grandparent = builder.setLayer(0).build();
 
         final TestWindowContainer parent = grandparent.addChildWindow();
@@ -433,8 +430,8 @@
     }
 
     @Test
-    public void testRemoveChild() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testRemoveChild() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
         final TestWindowContainer child1 = root.addChildWindow();
         final TestWindowContainer child2 = root.addChildWindow();
@@ -460,7 +457,7 @@
     }
 
     @Test
-    public void testGetOrientation_childSpecified() throws Exception {
+    public void testGetOrientation_childSpecified() {
         testGetOrientation_childSpecifiedConfig(false, SCREEN_ORIENTATION_LANDSCAPE,
             SCREEN_ORIENTATION_LANDSCAPE);
         testGetOrientation_childSpecifiedConfig(false, SCREEN_ORIENTATION_UNSET,
@@ -469,7 +466,7 @@
 
     private void testGetOrientation_childSpecifiedConfig(boolean childVisible, int childOrientation,
         int expectedOrientation) {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
         root.setFillsParent(true);
 
@@ -486,16 +483,16 @@
     }
 
     @Test
-    public void testGetOrientation_Unset() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testGetOrientation_Unset() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).setIsVisible(true).build();
         // Unspecified well because we didn't specify anything...
         assertEquals(SCREEN_ORIENTATION_UNSPECIFIED, root.getOrientation());
     }
 
     @Test
-    public void testGetOrientation_InvisibleParentUnsetVisibleChildren() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testGetOrientation_InvisibleParentUnsetVisibleChildren() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).setIsVisible(true).build();
 
         builder.setIsVisible(false).setLayer(-1);
@@ -516,12 +513,11 @@
         visibleUnset.setOrientation(SCREEN_ORIENTATION_UNSET);
         assertEquals(SCREEN_ORIENTATION_UNSET, visibleUnset.getOrientation());
         assertEquals(SCREEN_ORIENTATION_LANDSCAPE, root.getOrientation());
-
     }
 
     @Test
-    public void testGetOrientation_setBehind() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testGetOrientation_setBehind() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).setIsVisible(true).build();
 
         builder.setIsVisible(true).setLayer(-1);
@@ -541,8 +537,8 @@
     }
 
     @Test
-    public void testGetOrientation_fillsParent() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testGetOrientation_fillsParent() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).setIsVisible(true).build();
 
         builder.setIsVisible(true).setLayer(-1);
@@ -577,8 +573,8 @@
     }
 
     @Test
-    public void testCompareTo() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testCompareTo() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.setLayer(0).build();
 
         final TestWindowContainer child1 = root.addChildWindow();
@@ -588,8 +584,6 @@
         final TestWindowContainer child2 = root.addChildWindow();
         final TestWindowContainer child21 = child2.addChildWindow();
         final TestWindowContainer child22 = child2.addChildWindow();
-        final TestWindowContainer child23 = child2.addChildWindow();
-        final TestWindowContainer child221 = child22.addChildWindow();
         final TestWindowContainer child222 = child22.addChildWindow();
         final TestWindowContainer child223 = child22.addChildWindow();
         final TestWindowContainer child2221 = child222.addChildWindow();
@@ -620,8 +614,8 @@
     }
 
     @Test
-    public void testPrefixOrderIndex() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testPrefixOrderIndex() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.build();
 
         final TestWindowContainer child1 = root.addChildWindow();
@@ -654,8 +648,8 @@
     }
 
     @Test
-    public void testPrefixOrder_addEntireSubtree() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testPrefixOrder_addEntireSubtree() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.build();
         final TestWindowContainer subtree = builder.build();
         final TestWindowContainer subtree2 = builder.build();
@@ -677,8 +671,8 @@
     }
 
     @Test
-    public void testPrefixOrder_remove() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testPrefixOrder_remove() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.build();
 
         final TestWindowContainer child1 = root.addChildWindow();
@@ -705,8 +699,8 @@
      * is invoked with overridden bounds.
      */
     @Test
-    public void testOnParentResizePropagation() throws Exception {
-        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder();
+    public void testOnParentResizePropagation() {
+        final TestWindowContainerBuilder builder = new TestWindowContainerBuilder(mWm);
         final TestWindowContainer root = builder.build();
 
         final TestWindowContainer child = root.addChildWindow();
@@ -731,7 +725,7 @@
     }
 
     /* Used so we can gain access to some protected members of the {@link WindowContainer} class */
-    private class TestWindowContainer extends WindowContainer<TestWindowContainer> {
+    private static class TestWindowContainer extends WindowContainer<TestWindowContainer> {
         private final int mLayer;
         private boolean mIsAnimating;
         private boolean mIsVisible;
@@ -745,7 +739,7 @@
          * Compares 2 window layers and returns -1 if the first is lesser than the second in terms
          * of z-order and 1 otherwise.
          */
-        private final Comparator<TestWindowContainer> mWindowSubLayerComparator = (w1, w2) -> {
+        private static final Comparator<TestWindowContainer> SUBLAYER_COMPARATOR = (w1, w2) -> {
             final int layer1 = w1.mLayer;
             final int layer2 = w2.mLayer;
             if (layer1 < layer2 || (layer1 == layer2 && layer2 < 0 )) {
@@ -753,12 +747,14 @@
                 // the negative one should go below others; the positive one should go above others.
                 return -1;
             }
+            if (layer1 == layer2) return 0;
             return 1;
         };
 
-        TestWindowContainer(int layer, boolean isAnimating, boolean isVisible,
-            Integer orientation) {
-            super(sWm);
+        TestWindowContainer(WindowManagerService wm, int layer, boolean isAnimating,
+                boolean isVisible, Integer orientation) {
+            super(wm);
+
             mLayer = layer;
             mIsAnimating = isAnimating;
             mIsVisible = isVisible;
@@ -775,18 +771,18 @@
         }
 
         TestWindowContainer addChildWindow(TestWindowContainer child) {
-            addChild(child, mWindowSubLayerComparator);
+            addChild(child, SUBLAYER_COMPARATOR);
             return child;
         }
 
         TestWindowContainer addChildWindow(TestWindowContainerBuilder childBuilder) {
             TestWindowContainer child = childBuilder.build();
-            addChild(child, mWindowSubLayerComparator);
+            addChild(child, SUBLAYER_COMPARATOR);
             return child;
         }
 
         TestWindowContainer addChildWindow() {
-            return addChildWindow(new TestWindowContainerBuilder().setLayer(1));
+            return addChildWindow(new TestWindowContainerBuilder(mService).setLayer(1));
         }
 
         @Override
@@ -830,14 +826,19 @@
         }
     }
 
-    private class TestWindowContainerBuilder {
+    private static class TestWindowContainerBuilder {
+        private final WindowManagerService mWm;
         private int mLayer;
         private boolean mIsAnimating;
         private boolean mIsVisible;
         private Integer mOrientation;
 
-        public TestWindowContainerBuilder() {
-            reset();
+        TestWindowContainerBuilder(WindowManagerService wm) {
+            mWm = wm;
+            mLayer = 0;
+            mIsAnimating = false;
+            mIsVisible = false;
+            mOrientation = null;
         }
 
         TestWindowContainerBuilder setLayer(int layer) {
@@ -860,27 +861,20 @@
             return this;
         }
 
-        TestWindowContainerBuilder reset() {
-            mLayer = 0;
-            mIsAnimating = false;
-            mIsVisible = false;
-            mOrientation = null;
-            return this;
-        }
-
         TestWindowContainer build() {
-            return new TestWindowContainer(mLayer, mIsAnimating, mIsVisible, mOrientation);
+            return new TestWindowContainer(mWm, mLayer, mIsAnimating, mIsVisible, mOrientation);
         }
     }
 
-    private class MockSurfaceBuildingContainer extends WindowContainer<WindowContainer> {
-        final SurfaceSession mSession = new SurfaceSession();
+    private static class MockSurfaceBuildingContainer extends WindowContainer<WindowContainer>
+            implements AutoCloseable {
+        private final SurfaceSession mSession = new SurfaceSession();
 
-        MockSurfaceBuildingContainer() {
-            super(sWm);
+        MockSurfaceBuildingContainer(WindowManagerService wm) {
+            super(wm);
         }
 
-        class MockSurfaceBuilder extends SurfaceControl.Builder {
+        static class MockSurfaceBuilder extends SurfaceControl.Builder {
             MockSurfaceBuilder(SurfaceSession ss) {
                 super(ss);
             }
@@ -895,5 +889,10 @@
         SurfaceControl.Builder makeChildSurface(WindowContainer child) {
             return new MockSurfaceBuilder(mSession);
         }
+
+        @Override
+        public void close() {
+            mSession.kill();
+        }
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowContainerTraversalTests.java b/services/tests/servicestests/src/com/android/server/wm/WindowContainerTraversalTests.java
index ffc8622..2b8b934 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowContainerTraversalTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowContainerTraversalTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -28,23 +28,23 @@
 import android.platform.test.annotations.Presubmit;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 import java.util.function.Consumer;
 
 /**
  * Tests for {@link WindowContainer#forAllWindows} and various implementations.
+ *
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:WindowContainerTraversalTests
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class WindowContainerTraversalTests extends WindowTestsBase {
 
     @Test
-    public void testDockedDividerPosition() throws Exception {
+    public void testDockedDividerPosition() {
         final WindowState splitScreenWindow = createWindowOnStack(null,
                 WINDOWING_MODE_SPLIT_SCREEN_PRIMARY, ACTIVITY_TYPE_STANDARD, TYPE_BASE_APPLICATION,
                 mDisplayContent, "splitScreenWindow");
@@ -52,7 +52,7 @@
                 WINDOWING_MODE_SPLIT_SCREEN_SECONDARY, ACTIVITY_TYPE_STANDARD,
                 TYPE_BASE_APPLICATION, mDisplayContent, "splitScreenSecondaryWindow");
 
-        sWm.mInputMethodTarget = splitScreenWindow;
+        mWm.mInputMethodTarget = splitScreenWindow;
 
         Consumer<WindowState> c = mock(Consumer.class);
         mDisplayContent.forAllWindows(c, false);
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowFrameTests.java b/services/tests/servicestests/src/com/android/server/wm/WindowFrameTests.java
index 7cd1314..b0c8d8b 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowFrameTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowFrameTests.java
@@ -11,14 +11,14 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
 
 import static android.view.DisplayCutout.BOUNDS_POSITION_TOP;
 import static android.view.DisplayCutout.fromBoundingRect;
-import static android.view.WindowManager.LayoutParams.FILL_PARENT;
+import static android.view.WindowManager.LayoutParams.MATCH_PARENT;
 import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION;
 
 import static org.junit.Assert.assertEquals;
@@ -33,33 +33,32 @@
 import android.view.WindowManager;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import com.android.server.wm.utils.WmDisplayCutout;
 
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Tests for the {@link WindowState#computeFrameLw} method and other window frame machinery.
  *
- * Build/Install/Run: bit FrameworksServicesTests:com.android.server.wm.WindowFrameTests
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:WindowFrameTests
  */
 @SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class WindowFrameTests extends WindowTestsBase {
 
     private WindowToken mWindowToken;
     private final IWindow mIWindow = new TestIWindow();
     private final Rect mEmptyRect = new Rect();
 
-    class WindowStateWithTask extends WindowState {
+    static class WindowStateWithTask extends WindowState {
         final Task mTask;
         boolean mDockedResizingForTest = false;
-        WindowStateWithTask(WindowManager.LayoutParams attrs, Task t) {
-            super(sWm, null, mIWindow, mWindowToken, null, 0, 0, attrs, 0, 0,
+        WindowStateWithTask(WindowManagerService wm, IWindow iWindow, WindowToken windowToken,
+                WindowManager.LayoutParams attrs, Task t) {
+            super(wm, null, iWindow, windowToken, null, 0, 0, attrs, 0, 0,
                     false /* ownerCanAddInternalSystemWindow */);
             mTask = t;
         }
@@ -73,14 +72,15 @@
         boolean isDockedResizing() {
             return mDockedResizingForTest;
         }
-    };
+    }
 
-    class TaskWithBounds extends Task {
+    private static class TaskWithBounds extends Task {
         final Rect mBounds;
         final Rect mInsetBounds = new Rect();
         boolean mFullscreenForTest = true;
-        TaskWithBounds(Rect bounds) {
-            super(0, mStubStack, 0, sWm, 0, false, new TaskDescription(), null);
+
+        TaskWithBounds(TaskStack stack, WindowManagerService wm, Rect bounds) {
+            super(0, stack, 0, wm, 0, false, new TaskDescription(), null);
             mBounds = bounds;
             setBounds(bounds);
         }
@@ -113,14 +113,12 @@
 
     @Before
     public void setUp() throws Exception {
-        super.setUp();
-
         // Just any non zero value.
-        sWm.mSystemDecorLayer = 10000;
+        mWm.mSystemDecorLayer = 10000;
 
         mWindowToken = WindowTestUtils.createTestAppWindowToken(
-                sWm.getDefaultDisplayContentLocked());
-        mStubStack = new TaskStack(sWm, 0, null);
+                mWm.getDefaultDisplayContentLocked());
+        mStubStack = new TaskStack(mWm, 0, null);
     }
 
     // Do not use this function directly in the tests below. Instead, use more explicit function
@@ -170,9 +168,10 @@
     }
 
     @Test
-    public void testLayoutInFullscreenTaskInsets() throws Exception {
-        Task task = new TaskWithBounds(null); // fullscreen task doesn't use bounds for computeFrame
-        WindowState w = createWindow(task, FILL_PARENT, FILL_PARENT);
+    public void testLayoutInFullscreenTaskInsets() {
+        // fullscreen task doesn't use bounds for computeFrame
+        final Task task = new TaskWithBounds(mStubStack, mWm, null);
+        WindowState w = createWindow(task, MATCH_PARENT, MATCH_PARENT);
         w.mAttrs.gravity = Gravity.LEFT | Gravity.TOP;
 
         final int bottomContentInset = 100;
@@ -227,9 +226,10 @@
     }
 
     @Test
-    public void testLayoutInFullscreenTaskNoInsets() throws Exception {
-        Task task = new TaskWithBounds(null); // fullscreen task doesn't use bounds for computeFrame
-        WindowState w = createWindow(task, FILL_PARENT, FILL_PARENT);
+    public void testLayoutInFullscreenTaskNoInsets() {
+        // fullscreen task doesn't use bounds for computeFrame
+        final Task task = new TaskWithBounds(mStubStack, mWm, null);
+        WindowState w = createWindow(task, MATCH_PARENT, MATCH_PARENT);
         w.mAttrs.gravity = Gravity.LEFT | Gravity.TOP;
 
         // With no insets or system decor all the frames incoming from PhoneWindowManager
@@ -307,7 +307,7 @@
 
     @Test
     public void testLayoutNonfullscreenTask() {
-        final DisplayInfo displayInfo = sWm.getDefaultDisplayContentLocked().getDisplayInfo();
+        final DisplayInfo displayInfo = mWm.getDefaultDisplayContentLocked().getDisplayInfo();
         final int logicalWidth = displayInfo.logicalWidth;
         final int logicalHeight = displayInfo.logicalHeight;
 
@@ -316,9 +316,9 @@
         final int taskRight = logicalWidth / 4 * 3;
         final int taskBottom = logicalHeight / 4 * 3;
         final Rect taskBounds = new Rect(taskLeft, taskTop, taskRight, taskBottom);
-        TaskWithBounds task = new TaskWithBounds(taskBounds);
+        final TaskWithBounds task = new TaskWithBounds(mStubStack, mWm, taskBounds);
         task.mFullscreenForTest = false;
-        WindowState w = createWindow(task, FILL_PARENT, FILL_PARENT);
+        WindowState w = createWindow(task, MATCH_PARENT, MATCH_PARENT);
         w.mAttrs.gravity = Gravity.LEFT | Gravity.TOP;
 
         final Rect pf = new Rect(0, 0, logicalWidth, logicalHeight);
@@ -367,7 +367,7 @@
     @Test
     public void testCalculatePolicyCrop() {
         final WindowStateWithTask w = createWindow(
-                new TaskWithBounds(null), FILL_PARENT, FILL_PARENT);
+                new TaskWithBounds(mStubStack, mWm, null), MATCH_PARENT, MATCH_PARENT);
         w.mAttrs.gravity = Gravity.LEFT | Gravity.TOP;
 
         final DisplayInfo displayInfo = w.getDisplayContent().getDisplayInfo();
@@ -423,7 +423,7 @@
     @Test
     public void testLayoutLetterboxedWindow() {
         // First verify task behavior in multi-window mode.
-        final DisplayInfo displayInfo = sWm.getDefaultDisplayContentLocked().getDisplayInfo();
+        final DisplayInfo displayInfo = mWm.getDefaultDisplayContentLocked().getDisplayInfo();
         final int logicalWidth = displayInfo.logicalWidth;
         final int logicalHeight = displayInfo.logicalHeight;
 
@@ -432,10 +432,10 @@
         final int taskRight = logicalWidth / 4 * 3;
         final int taskBottom = logicalHeight / 4 * 3;
         final Rect taskBounds = new Rect(taskLeft, taskTop, taskRight, taskBottom);
-        TaskWithBounds task = new TaskWithBounds(taskBounds);
+        final TaskWithBounds task = new TaskWithBounds(mStubStack, mWm, taskBounds);
         task.mInsetBounds.set(taskLeft, taskTop, taskRight, taskBottom);
         task.mFullscreenForTest = false;
-        WindowState w = createWindow(task, FILL_PARENT, FILL_PARENT);
+        WindowState w = createWindow(task, MATCH_PARENT, MATCH_PARENT);
         w.mAttrs.gravity = Gravity.LEFT | Gravity.TOP;
 
         final Rect pf = new Rect(0, 0, logicalWidth, logicalHeight);
@@ -467,8 +467,8 @@
     @Test
     public void testDisplayCutout() {
         // Regular fullscreen task and window
-        Task task = new TaskWithBounds(null);
-        WindowState w = createWindow(task, FILL_PARENT, FILL_PARENT);
+        final Task task = new TaskWithBounds(mStubStack, mWm, null);
+        WindowState w = createWindow(task, MATCH_PARENT, MATCH_PARENT);
         w.mAttrs.gravity = Gravity.LEFT | Gravity.TOP;
 
         final Rect pf = new Rect(0, 0, 1000, 2000);
@@ -491,10 +491,11 @@
     @Test
     public void testDisplayCutout_tempInsetBounds() {
         // Regular fullscreen task and window
-        TaskWithBounds task = new TaskWithBounds(new Rect(0, -500, 1000, 1500));
+        final TaskWithBounds task = new TaskWithBounds(mStubStack, mWm,
+                new Rect(0, -500, 1000, 1500));
         task.mFullscreenForTest = false;
         task.mInsetBounds.set(0, 0, 1000, 2000);
-        WindowState w = createWindow(task, FILL_PARENT, FILL_PARENT);
+        WindowState w = createWindow(task, MATCH_PARENT, MATCH_PARENT);
         w.mAttrs.gravity = Gravity.LEFT | Gravity.TOP;
 
         final Rect pf = new Rect(0, -500, 1000, 1500);
@@ -519,7 +520,6 @@
         attrs.width = width;
         attrs.height = height;
 
-        return new WindowStateWithTask(attrs, task);
+        return new WindowStateWithTask(mWm, mIWindow, mWindowToken, attrs, task);
     }
-
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowManagerServiceRule.java b/services/tests/servicestests/src/com/android/server/wm/WindowManagerServiceRule.java
index 012c4be..4e75ec9 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowManagerServiceRule.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowManagerServiceRule.java
@@ -19,6 +19,8 @@
 import static android.testing.DexmakerShareClassLoaderRule.runWithDexmakerShareClassLoader;
 import static android.view.Display.DEFAULT_DISPLAY;
 
+import static androidx.test.platform.app.InstrumentationRegistry.getInstrumentation;
+
 import static com.android.server.wm.WindowManagerDebugConfig.TAG_WM;
 
 import static org.mockito.ArgumentMatchers.any;
@@ -51,8 +53,6 @@
 import java.util.ArrayList;
 import java.util.List;
 
-import androidx.test.InstrumentationRegistry;
-
 /**
  * A test rule that sets up a fresh WindowManagerService instance before each test and makes sure
  * to properly tear it down after.
@@ -89,7 +89,7 @@
             }
 
             private void setUp() {
-                final Context context = InstrumentationRegistry.getTargetContext();
+                final Context context = getInstrumentation().getTargetContext();
 
                 removeServices();
 
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowManagerServiceRuleTest.java b/services/tests/servicestests/src/com/android/server/wm/WindowManagerServiceRuleTest.java
index 570a853..343d359 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowManagerServiceRuleTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowManagerServiceRuleTest.java
@@ -22,13 +22,14 @@
 import android.platform.test.annotations.Presubmit;
 
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Rule;
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
-@RunWith(AndroidJUnit4.class)
+/**
+ * Build/InstallRun:
+ *  atest FrameworksServicesTests:WindowManagerServiceRuleTest
+ */
 @Presubmit
 @SmallTest
 public class WindowManagerServiceRuleTest {
@@ -40,4 +41,4 @@
     public void testWindowManagerSetUp() {
         assertThat(mRule.getWindowManagerService(), notNullValue());
     }
-}
\ No newline at end of file
+}
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowStateTests.java b/services/tests/servicestests/src/com/android/server/wm/WindowStateTests.java
index 3637baf..118ce89 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowStateTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowStateTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -58,32 +58,28 @@
 import android.view.SurfaceControl;
 import android.view.WindowManager;
 
+import androidx.test.filters.FlakyTest;
+import androidx.test.filters.SmallTest;
+
 import com.android.server.wm.utils.WmDisplayCutout;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
-import java.util.Arrays;
 import java.util.LinkedList;
 
-import androidx.test.filters.FlakyTest;
-import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
-
 /**
  * Tests for the {@link WindowState} class.
  *
- * atest FrameworksServicesTests:com.android.server.wm.WindowStateTests
+ * Build/Install/Run:
+ *  atest FrameworksServicesTests:WindowStateTests
  */
-@SmallTest
 @FlakyTest(bugId = 74078662)
-// TODO(b/116597907): Re-enable this test in postsubmit after the bug is fixed.
-// @Presubmit
-@RunWith(AndroidJUnit4.class)
+@SmallTest
+@Presubmit
 public class WindowStateTests extends WindowTestsBase {
 
     @Test
-    public void testIsParentWindowHidden() throws Exception {
+    public void testIsParentWindowHidden() {
         final WindowState parentWindow = createWindow(null, TYPE_APPLICATION, "parentWindow");
         final WindowState child1 = createWindow(parentWindow, FIRST_SUB_WINDOW, "child1");
         final WindowState child2 = createWindow(parentWindow, FIRST_SUB_WINDOW, "child2");
@@ -98,11 +94,10 @@
         assertFalse(parentWindow.isParentWindowHidden());
         assertFalse(child1.isParentWindowHidden());
         assertFalse(child2.isParentWindowHidden());
-
     }
 
     @Test
-    public void testIsChildWindow() throws Exception {
+    public void testIsChildWindow() {
         final WindowState parentWindow = createWindow(null, TYPE_APPLICATION, "parentWindow");
         final WindowState child1 = createWindow(parentWindow, FIRST_SUB_WINDOW, "child1");
         final WindowState child2 = createWindow(parentWindow, FIRST_SUB_WINDOW, "child2");
@@ -115,7 +110,7 @@
     }
 
     @Test
-    public void testHasChild() throws Exception {
+    public void testHasChild() {
         final WindowState win1 = createWindow(null, TYPE_APPLICATION, "win1");
         final WindowState win11 = createWindow(win1, FIRST_SUB_WINDOW, "win11");
         final WindowState win12 = createWindow(win1, FIRST_SUB_WINDOW, "win12");
@@ -136,7 +131,7 @@
     }
 
     @Test
-    public void testGetParentWindow() throws Exception {
+    public void testGetParentWindow() {
         final WindowState parentWindow = createWindow(null, TYPE_APPLICATION, "parentWindow");
         final WindowState child1 = createWindow(parentWindow, FIRST_SUB_WINDOW, "child1");
         final WindowState child2 = createWindow(parentWindow, FIRST_SUB_WINDOW, "child2");
@@ -157,7 +152,7 @@
     }
 
     @Test
-    public void testGetTopParentWindow() throws Exception {
+    public void testGetTopParentWindow() {
         final WindowState root = createWindow(null, TYPE_APPLICATION, "root");
         final WindowState child1 = createWindow(root, FIRST_SUB_WINDOW, "child1");
         final WindowState child2 = createWindow(child1, FIRST_SUB_WINDOW, "child2");
@@ -183,7 +178,7 @@
     }
 
     @Test
-    public void testCanBeImeTarget() throws Exception {
+    public void testCanBeImeTarget() {
         final WindowState appWindow = createWindow(null, TYPE_APPLICATION, "appWindow");
         final WindowState imeWindow = createWindow(null, TYPE_INPUT_METHOD, "imeWindow");
 
@@ -219,7 +214,7 @@
     }
 
     @Test
-    public void testGetWindow() throws Exception {
+    public void testGetWindow() {
         final WindowState root = createWindow(null, TYPE_APPLICATION, "root");
         final WindowState mediaChild = createWindow(root, TYPE_APPLICATION_MEDIA, "mediaChild");
         final WindowState mediaOverlayChild = createWindow(root,
@@ -231,7 +226,7 @@
         final WindowState aboveSubPanelChild = createWindow(root,
                 TYPE_APPLICATION_ABOVE_SUB_PANEL, "aboveSubPanelChild");
 
-        final LinkedList<WindowState> windows = new LinkedList();
+        final LinkedList<WindowState> windows = new LinkedList<>();
 
         root.getWindow(w -> {
             windows.addLast(w);
@@ -249,7 +244,7 @@
     }
 
     @Test
-    public void testPrepareWindowToDisplayDuringRelayout() throws Exception {
+    public void testPrepareWindowToDisplayDuringRelayout() {
         testPrepareWindowToDisplayDuringRelayout(false /*wasVisible*/);
         testPrepareWindowToDisplayDuringRelayout(true /*wasVisible*/);
 
@@ -262,14 +257,14 @@
         final WindowState second = createWindow(null, TYPE_APPLICATION, appWindowToken, "second");
         second.mAttrs.flags |= WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON;
 
-        reset(mPowerManagerWrapper);
+        reset(sPowerManagerWrapper);
         first.prepareWindowToDisplayDuringRelayout(false /*wasVisible*/);
-        verify(mPowerManagerWrapper, never()).wakeUp(anyLong(), anyString());
+        verify(sPowerManagerWrapper, never()).wakeUp(anyLong(), anyString());
         assertTrue(appWindowToken.canTurnScreenOn());
 
-        reset(mPowerManagerWrapper);
+        reset(sPowerManagerWrapper);
         second.prepareWindowToDisplayDuringRelayout(false /*wasVisible*/);
-        verify(mPowerManagerWrapper).wakeUp(anyLong(), anyString());
+        verify(sPowerManagerWrapper).wakeUp(anyLong(), anyString());
         assertFalse(appWindowToken.canTurnScreenOn());
 
         // Call prepareWindowToDisplayDuringRelayout for two window that have FLAG_TURN_SCREEN_ON
@@ -278,14 +273,14 @@
         first.mAttrs.flags |= WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON;
         second.mAttrs.flags |= WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON;
 
-        reset(mPowerManagerWrapper);
+        reset(sPowerManagerWrapper);
         first.prepareWindowToDisplayDuringRelayout(false /*wasVisible*/);
-        verify(mPowerManagerWrapper).wakeUp(anyLong(), anyString());
+        verify(sPowerManagerWrapper).wakeUp(anyLong(), anyString());
         assertFalse(appWindowToken.canTurnScreenOn());
 
-        reset(mPowerManagerWrapper);
+        reset(sPowerManagerWrapper);
         second.prepareWindowToDisplayDuringRelayout(false /*wasVisible*/);
-        verify(mPowerManagerWrapper, never()).wakeUp(anyLong(), anyString());
+        verify(sPowerManagerWrapper, never()).wakeUp(anyLong(), anyString());
         assertFalse(appWindowToken.canTurnScreenOn());
 
         // Call prepareWindowToDisplayDuringRelayout for a windows that are not children of an
@@ -299,17 +294,17 @@
         firstWindow.mAttrs.flags |= WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON;
         secondWindow.mAttrs.flags |= WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON;
 
-        reset(mPowerManagerWrapper);
+        reset(sPowerManagerWrapper);
         firstWindow.prepareWindowToDisplayDuringRelayout(false /*wasVisible*/);
-        verify(mPowerManagerWrapper).wakeUp(anyLong(), anyString());
+        verify(sPowerManagerWrapper).wakeUp(anyLong(), anyString());
 
-        reset(mPowerManagerWrapper);
+        reset(sPowerManagerWrapper);
         secondWindow.prepareWindowToDisplayDuringRelayout(false /*wasVisible*/);
-        verify(mPowerManagerWrapper).wakeUp(anyLong(), anyString());
+        verify(sPowerManagerWrapper).wakeUp(anyLong(), anyString());
     }
 
     @Test
-    public void testCanAffectSystemUiFlags() throws Exception {
+    public void testCanAffectSystemUiFlags() {
         final WindowState app = createWindow(null, TYPE_APPLICATION, "app");
         app.mToken.setHidden(false);
         assertTrue(app.canAffectSystemUiFlags());
@@ -318,11 +313,10 @@
         app.mToken.setHidden(false);
         app.mAttrs.alpha = 0.0f;
         assertFalse(app.canAffectSystemUiFlags());
-
     }
 
     @Test
-    public void testCanAffectSystemUiFlags_disallow() throws Exception {
+    public void testCanAffectSystemUiFlags_disallow() {
         final WindowState app = createWindow(null, TYPE_APPLICATION, "app");
         app.mToken.setHidden(false);
         assertTrue(app.canAffectSystemUiFlags());
@@ -331,7 +325,7 @@
     }
 
     @Test
-    public void testIsSelfOrAncestorWindowAnimating() throws Exception {
+    public void testIsSelfOrAncestorWindowAnimating() {
         final WindowState root = createWindow(null, TYPE_APPLICATION, "root");
         final WindowState child1 = createWindow(root, FIRST_SUB_WINDOW, "child1");
         final WindowState child2 = createWindow(child1, FIRST_SUB_WINDOW, "child2");
@@ -344,7 +338,7 @@
     }
 
     @Test
-    public void testLayoutSeqResetOnReparent() throws Exception {
+    public void testLayoutSeqResetOnReparent() {
         final WindowState app = createWindow(null, TYPE_APPLICATION, "app");
         app.mLayoutSeq = 1;
         mDisplayContent.mLayoutSeq = 1;
@@ -355,7 +349,7 @@
     }
 
     @Test
-    public void testDisplayIdUpdatedOnReparent() throws Exception {
+    public void testDisplayIdUpdatedOnReparent() {
         final WindowState app = createWindow(null, TYPE_APPLICATION, "app");
         // fake a different display
         app.mInputWindowHandle.displayId = mDisplayContent.getDisplayId() + 1;
@@ -418,11 +412,11 @@
     }
 
     private void testPrepareWindowToDisplayDuringRelayout(boolean wasVisible) {
-        reset(mPowerManagerWrapper);
+        reset(sPowerManagerWrapper);
         final WindowState root = createWindow(null, TYPE_APPLICATION, "root");
         root.mAttrs.flags |= WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON;
 
         root.prepareWindowToDisplayDuringRelayout(wasVisible /*wasVisible*/);
-        verify(mPowerManagerWrapper).wakeUp(anyLong(), anyString());
+        verify(sPowerManagerWrapper).wakeUp(anyLong(), anyString());
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowTestUtils.java b/services/tests/servicestests/src/com/android/server/wm/WindowTestUtils.java
index e155be4..9e12f02 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowTestUtils.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowTestUtils.java
@@ -11,11 +11,26 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
 
+import static android.app.AppOpsManager.OP_NONE;
+import static android.content.pm.ActivityInfo.RESIZE_MODE_UNRESIZEABLE;
+import static android.content.pm.ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED;
+
+import static com.android.server.wm.WindowContainer.POSITION_TOP;
+
+import static org.mockito.Mockito.any;
+import static org.mockito.Mockito.anyBoolean;
+import static org.mockito.Mockito.anyFloat;
+import static org.mockito.Mockito.anyInt;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
 import android.app.ActivityManager;
 import android.content.Context;
 import android.content.res.Configuration;
@@ -26,24 +41,9 @@
 import android.view.IApplicationToken;
 import android.view.IWindow;
 import android.view.Surface;
-import android.view.SurfaceControl;
 import android.view.SurfaceControl.Transaction;
 import android.view.WindowManager;
 
-import static android.app.AppOpsManager.OP_NONE;
-import static android.content.pm.ActivityInfo.RESIZE_MODE_UNRESIZEABLE;
-import static android.content.pm.ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED;
-
-import static com.android.server.wm.WindowContainer.POSITION_TOP;
-import static org.mockito.Mockito.any;
-import static org.mockito.Mockito.anyBoolean;
-import static org.mockito.Mockito.anyFloat;
-import static org.mockito.Mockito.anyInt;
-import static org.mockito.Mockito.doAnswer;
-import static org.mockito.Mockito.doReturn;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.when;
-
 import org.mockito.invocation.InvocationOnMock;
 
 /**
@@ -277,35 +277,33 @@
      */
     public static class TestTaskWindowContainerController extends TaskWindowContainerController {
 
+        static final TaskWindowContainerListener NOP_LISTENER = new TaskWindowContainerListener() {
+            @Override
+            public void registerConfigurationChangeListener(
+                    ConfigurationContainerListener listener) {
+            }
+
+            @Override
+            public void unregisterConfigurationChangeListener(
+                    ConfigurationContainerListener listener) {
+            }
+
+            @Override
+            public void onSnapshotChanged(ActivityManager.TaskSnapshot snapshot) {
+            }
+
+            @Override
+            public void requestResize(Rect bounds, int resizeMode) {
+            }
+        };
+
         TestTaskWindowContainerController(WindowTestsBase testsBase) {
             this(testsBase.createStackControllerOnDisplay(testsBase.mDisplayContent));
         }
 
         TestTaskWindowContainerController(StackWindowController stackController) {
-            super(sNextTaskId++, new TaskWindowContainerListener() {
-                        @Override
-                        public void registerConfigurationChangeListener(
-                                ConfigurationContainerListener listener) {
-
-                        }
-
-                        @Override
-                        public void unregisterConfigurationChangeListener(
-                                ConfigurationContainerListener listener) {
-
-                        }
-
-                        @Override
-                        public void onSnapshotChanged(ActivityManager.TaskSnapshot snapshot) {
-
-                        }
-
-                        @Override
-                        public void requestResize(Rect bounds, int resizeMode) {
-
-                        }
-                    }, stackController, 0 /* userId */, null /* bounds */, RESIZE_MODE_UNRESIZEABLE,
-                    false /* supportsPictureInPicture */, true /* toTop*/,
+            super(sNextTaskId++, NOP_LISTENER, stackController, 0 /* userId */, null /* bounds */,
+                    RESIZE_MODE_UNRESIZEABLE, false /* supportsPictureInPicture */, true /* toTop*/,
                     true /* showForAllUsers */, new ActivityManager.TaskDescription(),
                     stackController.mService);
         }
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowTestsBase.java b/services/tests/servicestests/src/com/android/server/wm/WindowTestsBase.java
index 73bb1c9..945cbb9 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowTestsBase.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowTestsBase.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -35,6 +35,8 @@
 import static android.view.WindowManager.LayoutParams.TYPE_STATUS_BAR;
 import static android.view.WindowManager.LayoutParams.TYPE_WALLPAPER;
 
+import static androidx.test.platform.app.InstrumentationRegistry.getInstrumentation;
+
 import static org.mockito.Mockito.mock;
 
 import android.content.Context;
@@ -52,13 +54,12 @@
 
 import org.junit.After;
 import org.junit.Before;
+import org.junit.BeforeClass;
 import org.junit.Rule;
 
 import java.util.HashSet;
 import java.util.LinkedList;
 
-import androidx.test.InstrumentationRegistry;
-
 /**
  * Common base class for window manager unit test classes.
  *
@@ -66,7 +67,8 @@
  */
 class WindowTestsBase {
     private static final String TAG = WindowTestsBase.class.getSimpleName();
-    WindowManagerService sWm = null;  // TODO(roosa): rename to mWm in follow-up CL
+
+    WindowManagerService mWm;
     private final IWindow mIWindow = new TestIWindow();
     private Session mMockSession;
     // The default display is removed in {@link #setUp} and then we iterate over all displays to
@@ -97,32 +99,36 @@
     @Rule
     public final WindowManagerServiceRule mWmRule = new WindowManagerServiceRule();
 
-    static WindowState.PowerManagerWrapper mPowerManagerWrapper;  // TODO(roosa): make non-static.
+    static WindowState.PowerManagerWrapper sPowerManagerWrapper;  // TODO(roosa): make non-static.
+
+    @BeforeClass
+    public static void setUpOnceBase() {
+        AttributeCache.init(getInstrumentation().getTargetContext());
+        sPowerManagerWrapper = mock(WindowState.PowerManagerWrapper.class);
+    }
 
     @Before
-    public void setUp() throws Exception {
+    public void setUpBase() {
         // If @Before throws an exception, the error isn't logged. This will make sure any failures
         // in the set up are clear. This can be removed when b/37850063 is fixed.
         try {
             mMockSession = mock(Session.class);
-            mPowerManagerWrapper = mock(WindowState.PowerManagerWrapper.class);
 
-            final Context context = InstrumentationRegistry.getTargetContext();
-            AttributeCache.init(context);
+            final Context context = getInstrumentation().getTargetContext();
 
-            sWm = mWmRule.getWindowManagerService();
+            mWm = mWmRule.getWindowManagerService();
             beforeCreateDisplay();
 
-            mWallpaperController = new WallpaperController(sWm);
+            mWallpaperController = new WallpaperController(mWm);
 
             context.getDisplay().getDisplayInfo(mDisplayInfo);
             mDisplayContent = createNewDisplay();
-            sWm.mDisplayEnabled = true;
-            sWm.mDisplayReady = true;
+            mWm.mDisplayEnabled = true;
+            mWm.mDisplayReady = true;
 
             // Set-up some common windows.
-            mCommonWindows = new HashSet();
-            synchronized (sWm.mGlobalLock) {
+            mCommonWindows = new HashSet<>();
+            synchronized (mWm.mGlobalLock) {
                 mWallpaperWindow = createCommonWindow(null, TYPE_WALLPAPER, "wallpaperWindow");
                 mImeWindow = createCommonWindow(null, TYPE_INPUT_METHOD, "mImeWindow");
                 mDisplayContent.mInputMethodWindow = mImeWindow;
@@ -154,7 +160,7 @@
     }
 
     @After
-    public void tearDown() throws Exception {
+    public void tearDownBase() {
         // If @After throws an exception, the error isn't logged. This will make sure any failures
         // in the tear down are clear. This can be removed when b/37850063 is fixed.
         try {
@@ -164,8 +170,8 @@
 
             final LinkedList<WindowState> nonCommonWindows = new LinkedList<>();
 
-            synchronized (sWm.mGlobalLock) {
-                sWm.mRoot.forAllWindows(w -> {
+            synchronized (mWm.mGlobalLock) {
+                mWm.mRoot.forAllWindows(w -> {
                     if (!mCommonWindows.contains(w)) {
                         nonCommonWindows.addLast(w);
                     }
@@ -175,18 +181,18 @@
                     nonCommonWindows.pollLast().removeImmediately();
                 }
 
-                for (int i = sWm.mRoot.mChildren.size() - 1; i >= 0; --i) {
-                    final DisplayContent displayContent = sWm.mRoot.mChildren.get(i);
+                for (int i = mWm.mRoot.mChildren.size() - 1; i >= 0; --i) {
+                    final DisplayContent displayContent = mWm.mRoot.mChildren.get(i);
                     if (!displayContent.isDefaultDisplay) {
                         displayContent.removeImmediately();
                     }
                 }
                 // Remove app transition & window freeze timeout callbacks to prevent unnecessary
                 // actions after test.
-                sWm.getDefaultDisplayContentLocked().mAppTransition
+                mWm.getDefaultDisplayContentLocked().mAppTransition
                         .removeAppTransitionTimeoutCallbacks();
-                sWm.mH.removeMessages(WindowManagerService.H.WINDOW_FREEZE_TIMEOUT);
-                sWm.mInputMethodTarget = null;
+                mWm.mH.removeMessages(WindowManagerService.H.WINDOW_FREEZE_TIMEOUT);
+                mWm.mInputMethodTarget = null;
             }
 
             // Wait until everything is really cleaned up.
@@ -198,7 +204,7 @@
     }
 
     private WindowState createCommonWindow(WindowState parent, int type, String name) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             final WindowState win = createWindow(parent, type, name);
             mCommonWindows.add(win);
             // Prevent common windows from been IMe targets
@@ -216,7 +222,7 @@
 
     private WindowToken createWindowToken(
             DisplayContent dc, int windowingMode, int activityType, int type) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             if (type < FIRST_APPLICATION_WINDOW || type > LAST_APPLICATION_WINDOW) {
                 return WindowTestUtils.createTestWindowToken(type, dc);
             }
@@ -241,7 +247,7 @@
     }
 
     WindowState createWindow(WindowState parent, int type, String name) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             return (parent == null)
                     ? createWindow(parent, type, mDisplayContent, name)
                     : createWindow(parent, type, parent.mToken, name);
@@ -250,14 +256,14 @@
 
     WindowState createWindowOnStack(WindowState parent, int windowingMode, int activityType,
             int type, DisplayContent dc, String name) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             final WindowToken token = createWindowToken(dc, windowingMode, activityType, type);
             return createWindow(parent, type, token, name);
         }
     }
 
     WindowState createAppWindow(Task task, int type, String name) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             final AppWindowToken token = WindowTestUtils.createTestAppWindowToken(mDisplayContent);
             task.addChild(token, 0);
             return createWindow(null, type, token, name);
@@ -265,7 +271,7 @@
     }
 
     WindowState createWindow(WindowState parent, int type, DisplayContent dc, String name) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             final WindowToken token = createWindowToken(
                     dc, WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD, type);
             return createWindow(parent, type, token, name);
@@ -274,7 +280,7 @@
 
     WindowState createWindow(WindowState parent, int type, DisplayContent dc, String name,
             boolean ownerCanAddInternalSystemWindow) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             final WindowToken token = createWindowToken(
                     dc, WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD, type);
             return createWindow(parent, type, token, name, 0 /* ownerId */,
@@ -283,7 +289,7 @@
     }
 
     WindowState createWindow(WindowState parent, int type, WindowToken token, String name) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             return createWindow(parent, type, token, name, 0 /* ownerId */,
                     false /* ownerCanAddInternalSystemWindow */);
         }
@@ -292,7 +298,7 @@
     WindowState createWindow(WindowState parent, int type, WindowToken token, String name,
             int ownerId, boolean ownerCanAddInternalSystemWindow) {
         return createWindow(parent, type, token, name, ownerId, ownerCanAddInternalSystemWindow,
-                sWm, mMockSession, mIWindow);
+                mWm, mMockSession, mIWindow);
     }
 
     static WindowState createWindow(WindowState parent, int type, WindowToken token,
@@ -305,7 +311,7 @@
             final WindowState w = new WindowState(service, session, iWindow, token, parent,
                     OP_NONE,
                     0, attrs, VISIBLE, ownerId, ownerCanAddInternalSystemWindow,
-                    mPowerManagerWrapper);
+                    sPowerManagerWrapper);
             // TODO: Probably better to make this call in the WindowState ctor to avoid errors with
             // adding it to the token...
             token.addWindow(w);
@@ -315,13 +321,13 @@
 
     /** Creates a {@link TaskStack} and adds it to the specified {@link DisplayContent}. */
     TaskStack createTaskStackOnDisplay(DisplayContent dc) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             return createStackControllerOnDisplay(dc).mContainer;
         }
     }
 
     StackWindowController createStackControllerOnDisplay(DisplayContent dc) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             return createStackControllerOnStackOnDisplay(
                     WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD, dc);
         }
@@ -329,13 +335,13 @@
 
     StackWindowController createStackControllerOnStackOnDisplay(
             int windowingMode, int activityType, DisplayContent dc) {
-        synchronized (sWm.mGlobalLock) {
+        synchronized (mWm.mGlobalLock) {
             final Configuration overrideConfig = new Configuration();
             overrideConfig.windowConfiguration.setWindowingMode(windowingMode);
             overrideConfig.windowConfiguration.setActivityType(activityType);
             final int stackId = ++sNextStackId;
             final StackWindowController controller = new StackWindowController(stackId, null,
-                    dc.getDisplayId(), true /* onTop */, new Rect(), sWm);
+                    dc.getDisplayId(), true /* onTop */, new Rect(), mWm);
             controller.onOverrideConfigurationChanged(overrideConfig);
             return controller;
         }
@@ -343,7 +349,7 @@
 
     /** Creates a {@link Task} and adds it to the specified {@link TaskStack}. */
     Task createTaskInStack(TaskStack stack, int userId) {
-        return WindowTestUtils.createTaskInStack(sWm, stack, userId);
+        return WindowTestUtils.createTaskInStack(mWm, stack, userId);
     }
 
     /** Creates a {@link DisplayContent} and adds it to the system. */
@@ -351,8 +357,8 @@
         final int displayId = sNextDisplayId++;
         final Display display = new Display(DisplayManagerGlobal.getInstance(), displayId,
                 mDisplayInfo, DEFAULT_DISPLAY_ADJUSTMENTS);
-        synchronized (sWm.mGlobalLock) {
-            return new DisplayContent(display, sWm, mWallpaperController,
+        synchronized (mWm.mGlobalLock) {
+            return new DisplayContent(display, mWm, mWallpaperController,
                     mock(DisplayWindowController.class));
         }
     }
@@ -375,20 +381,19 @@
         final int displayId = sNextDisplayId++;
         final Display display = new Display(DisplayManagerGlobal.getInstance(), displayId,
                 displayInfo, DEFAULT_DISPLAY_ADJUSTMENTS);
-        final DisplayWindowController dcw = new DisplayWindowController(display, sWm);
-        synchronized (sWm.mGlobalLock) {
+        final DisplayWindowController dcw = new DisplayWindowController(display, mWm);
+        synchronized (mWm.mGlobalLock) {
             // Display creation is driven by DisplayWindowController via ActivityStackSupervisor.
             // We skip those steps here.
-            return sWm.mRoot.createDisplayContent(display, dcw);
+            return mWm.mRoot.createDisplayContent(display, dcw);
         }
     }
 
     /** Creates a {@link com.android.server.wm.WindowTestUtils.TestWindowState} */
     WindowTestUtils.TestWindowState createWindowState(WindowManager.LayoutParams attrs,
             WindowToken token) {
-        synchronized (sWm.mGlobalLock) {
-            return new WindowTestUtils.TestWindowState(sWm, mMockSession, mIWindow, attrs, token);
+        synchronized (mWm.mGlobalLock) {
+            return new WindowTestUtils.TestWindowState(mWm, mMockSession, mIWindow, attrs, token);
         }
     }
-
 }
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowTokenTests.java b/services/tests/servicestests/src/com/android/server/wm/WindowTokenTests.java
index 3732486..3048f1a 100644
--- a/services/tests/servicestests/src/com/android/server/wm/WindowTokenTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/WindowTokenTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -30,25 +30,22 @@
 
 import androidx.test.filters.FlakyTest;
 import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Test;
-import org.junit.runner.RunWith;
 
 /**
  * Tests for the {@link WindowToken} class.
  *
  * Build/Install/Run:
- *  bit FrameworksServicesTests:com.android.server.wm.WindowTokenTests
+ *  atest FrameworksServicesTests:WindowTokenTests
  */
-@SmallTest
 @FlakyTest(bugId = 74078662)
+@SmallTest
 @Presubmit
-@RunWith(AndroidJUnit4.class)
 public class WindowTokenTests extends WindowTestsBase {
 
     @Test
-    public void testAddWindow() throws Exception {
+    public void testAddWindow() {
         final WindowTestUtils.TestWindowToken token =
                 WindowTestUtils.createTestWindowToken(0, mDisplayContent);
 
@@ -78,7 +75,7 @@
     }
 
     @Test
-    public void testChildRemoval() throws Exception {
+    public void testChildRemoval() {
         final DisplayContent dc = mDisplayContent;
         final WindowTestUtils.TestWindowToken token = WindowTestUtils.createTestWindowToken(0, dc);
 
@@ -102,7 +99,7 @@
      * Tokens should only be removed from the system when all their windows are gone.
      */
     @Test
-    public void testTokenRemovalProcess() throws Exception {
+    public void testTokenRemovalProcess() {
         final WindowTestUtils.TestWindowToken token = WindowTestUtils.createTestWindowToken(
                 TYPE_TOAST, mDisplayContent, true /* persistOnEmpty */);
 
diff --git a/services/tests/servicestests/src/com/android/server/wm/WindowTracingTest.java b/services/tests/servicestests/src/com/android/server/wm/WindowTracingTest.java
deleted file mode 100644
index 01b7c4f..0000000
--- a/services/tests/servicestests/src/com/android/server/wm/WindowTracingTest.java
+++ /dev/null
@@ -1,198 +0,0 @@
-/*
- * Copyright (C) 2017 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.android.server.wm;
-
-import static org.junit.Assert.assertArrayEquals;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.ArgumentMatchers.eq;
-import static org.mockito.Mockito.doAnswer;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.verify;
-import static org.mockito.Mockito.verifyZeroInteractions;
-
-import android.content.Context;
-import android.platform.test.annotations.Presubmit;
-import android.util.proto.ProtoOutputStream;
-
-import androidx.test.InstrumentationRegistry;
-import androidx.test.filters.FlakyTest;
-import androidx.test.filters.SmallTest;
-import androidx.test.runner.AndroidJUnit4;
-
-import com.android.internal.util.Preconditions;
-import com.android.server.wm.WindowManagerTraceProto;
-
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Ignore;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.InputStream;
-import java.io.PrintWriter;
-import java.nio.charset.StandardCharsets;
-
-/**
- * Test class for {@link WindowTracing}.
- *
- * Build/Install/Run:
- *  bit FrameworksServicesTests:com.android.server.wm.WindowTracingTest
- */
-@SmallTest
-@FlakyTest(bugId = 74078662)
-// TODO(b/116597907): Re-enable this test in postsubmit after the bug is fixed.
-// @Presubmit
-@RunWith(AndroidJUnit4.class)
-public class WindowTracingTest extends WindowTestsBase {
-
-    private static final byte[] MAGIC_HEADER = new byte[] {
-        0x9, 0x57, 0x49, 0x4e, 0x54, 0x52, 0x41, 0x43, 0x45,
-    };
-
-    private Context mTestContext;
-    private WindowTracing mWindowTracing;
-    private WindowManagerService mWmMock;
-    private File mFile;
-
-    @Override
-    @Before
-    public void setUp() throws Exception {
-        super.setUp();
-
-        mWmMock = mock(WindowManagerService.class);
-
-        mTestContext = InstrumentationRegistry.getContext();
-
-        mFile = mTestContext.getFileStreamPath("tracing_test.dat");
-        mFile.delete();
-
-        mWindowTracing = new WindowTracing(mFile);
-    }
-
-    @Test
-    public void isEnabled_returnsFalseByDefault() throws Exception {
-        assertFalse(mWindowTracing.isEnabled());
-    }
-
-    @Test
-    public void isEnabled_returnsTrueAfterStart() throws Exception {
-        mWindowTracing.startTrace(mock(PrintWriter.class));
-        assertTrue(mWindowTracing.isEnabled());
-    }
-
-    @Test
-    public void isEnabled_returnsFalseAfterStop() throws Exception {
-        mWindowTracing.startTrace(mock(PrintWriter.class));
-        mWindowTracing.stopTrace(mock(PrintWriter.class));
-        assertFalse(mWindowTracing.isEnabled());
-    }
-
-    @Test
-    public void trace_discared_whenNotTracing() throws Exception {
-        mWindowTracing.traceStateLocked("where", mWmMock);
-        verifyZeroInteractions(mWmMock);
-    }
-
-    @Test
-    public void trace_dumpsWindowManagerState_whenTracing() throws Exception {
-        mWindowTracing.startTrace(mock(PrintWriter.class));
-        mWindowTracing.traceStateLocked("where", mWmMock);
-
-        verify(mWmMock).writeToProtoLocked(any(), eq(true));
-    }
-
-    @Test
-    public void traceFile_startsWithMagicHeader() throws Exception {
-        mWindowTracing.startTrace(mock(PrintWriter.class));
-        mWindowTracing.stopTrace(mock(PrintWriter.class));
-
-        byte[] header = new byte[MAGIC_HEADER.length];
-        try (InputStream is = new FileInputStream(mFile)) {
-            assertEquals(MAGIC_HEADER.length, is.read(header));
-            assertArrayEquals(MAGIC_HEADER, header);
-        }
-    }
-
-    @Test
-    @Ignore("Figure out why this test is crashing when setting up mWmMock.")
-    public void tracing_endsUpInFile() throws Exception {
-        mWindowTracing.startTrace(mock(PrintWriter.class));
-
-        doAnswer((inv) -> {
-            inv.<ProtoOutputStream>getArgument(0).write(
-                    WindowManagerTraceProto.WHERE, "TEST_WM_PROTO");
-            return null;
-        }).when(mWmMock).writeToProtoLocked(any(), any());
-        mWindowTracing.traceStateLocked("TEST_WHERE", mWmMock);
-
-        mWindowTracing.stopTrace(mock(PrintWriter.class));
-
-        byte[] file = new byte[1000];
-        int fileLength;
-        try (InputStream is = new FileInputStream(mFile)) {
-            fileLength = is.read(file);
-            assertTrue(containsBytes(file, fileLength,
-                    "TEST_WHERE".getBytes(StandardCharsets.UTF_8)));
-            assertTrue(containsBytes(file, fileLength,
-                    "TEST_WM_PROTO".getBytes(StandardCharsets.UTF_8)));
-        }
-    }
-
-    @Override
-    @After
-    public void tearDown() throws Exception {
-        super.tearDown();
-
-        mFile.delete();
-    }
-
-    /** Return true if {@code needle} appears anywhere in {@code haystack[0..length]} */
-    boolean containsBytes(byte[] haystack, int haystackLenght, byte[] needle) {
-        Preconditions.checkArgument(haystackLenght > 0);
-        Preconditions.checkArgument(needle.length > 0);
-
-        outer: for (int i = 0; i <= haystackLenght - needle.length; i++) {
-            for (int j = 0; j < needle.length; j++) {
-                if (haystack[i+j] != needle[j]) {
-                    continue outer;
-                }
-            }
-            return true;
-        }
-        return false;
-    }
-
-    @Test
-    public void test_containsBytes() {
-        byte[] haystack = "hello_world".getBytes(StandardCharsets.UTF_8);
-        assertTrue(containsBytes(haystack, haystack.length,
-                "hello".getBytes(StandardCharsets.UTF_8)));
-        assertTrue(containsBytes(haystack, haystack.length,
-                "world".getBytes(StandardCharsets.UTF_8)));
-        assertFalse(containsBytes(haystack, 6,
-                "world".getBytes(StandardCharsets.UTF_8)));
-        assertFalse(containsBytes(haystack, haystack.length,
-                "world_".getBytes(StandardCharsets.UTF_8)));
-        assertFalse(containsBytes(haystack, haystack.length,
-                "absent".getBytes(StandardCharsets.UTF_8)));
-    }
-}
diff --git a/services/tests/servicestests/src/com/android/server/wm/ZOrderingTests.java b/services/tests/servicestests/src/com/android/server/wm/ZOrderingTests.java
index 3a8c4ae..32e4e02 100644
--- a/services/tests/servicestests/src/com/android/server/wm/ZOrderingTests.java
+++ b/services/tests/servicestests/src/com/android/server/wm/ZOrderingTests.java
@@ -11,7 +11,7 @@
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
- * limitations under the License
+ * limitations under the License.
  */
 
 package com.android.server.wm;
@@ -38,27 +38,30 @@
 import android.view.SurfaceControl;
 import android.view.SurfaceSession;
 
+import androidx.test.filters.FlakyTest;
+import androidx.test.filters.SmallTest;
+
 import org.junit.After;
 import org.junit.Test;
 
 import java.util.HashMap;
 import java.util.LinkedList;
 
-import androidx.test.filters.FlakyTest;
-import androidx.test.filters.SmallTest;
-
 /**
- * Tests for the {@link WindowLayersController} class.
+ * Tests for the {@link DisplayContent#assignChildLayers(SurfaceControl.Transaction)} method.
  *
  * Build/Install/Run:
- *  atest FrameworksServicesTests:com.android.server.wm.ZOrderingTests
+ *  atest FrameworksServicesTests:ZOrderingTests
  */
-@SmallTest
 @FlakyTest(bugId = 74078662)
+@SmallTest
 @Presubmit
 public class ZOrderingTests extends WindowTestsBase {
 
-    private class LayerRecordingTransaction extends SurfaceControl.Transaction {
+    private static class LayerRecordingTransaction extends SurfaceControl.Transaction {
+        // We have WM use our Hierarchy recording subclass of SurfaceControl.Builder
+        // such that we can keep track of the parents of Surfaces as they are constructed.
+        private final HashMap<SurfaceControl, SurfaceControl> mParentFor = new HashMap<>();
         HashMap<SurfaceControl, Integer> mLayersForControl = new HashMap<>();
         HashMap<SurfaceControl, SurfaceControl> mRelativeLayersForControl = new HashMap<>();
 
@@ -85,17 +88,28 @@
         private SurfaceControl getRelativeLayer(SurfaceControl sc) {
             return mRelativeLayersForControl.get(sc);
         }
+
+        void addParentFor(SurfaceControl child, SurfaceControl parent) {
+            mParentFor.put(child, parent);
+        }
+
+        SurfaceControl getParentFor(SurfaceControl child) {
+            return mParentFor.get(child);
+        }
+
+        @Override
+        public void close() {
+
+        }
     }
 
-    // We have WM use our Hierarchy recording subclass of SurfaceControl.Builder
-    // such that we can keep track of the parents of Surfaces as they are constructed.
-    private HashMap<SurfaceControl, SurfaceControl> mParentFor = new HashMap<>();
+    private static class HierarchyRecorder extends SurfaceControl.Builder {
+        private LayerRecordingTransaction mTransaction;
+        private SurfaceControl mPendingParent;
 
-    private class HierarchyRecorder extends SurfaceControl.Builder {
-        SurfaceControl mPendingParent;
-
-        HierarchyRecorder(SurfaceSession s) {
+        HierarchyRecorder(SurfaceSession s, LayerRecordingTransaction transaction) {
             super(s);
+            mTransaction = transaction;
         }
 
         @Override
@@ -106,16 +120,26 @@
 
         @Override
         public SurfaceControl build() {
-            SurfaceControl sc = super.build();
-            mParentFor.put(sc, mPendingParent);
+            final SurfaceControl sc = super.build();
+            mTransaction.addParentFor(sc, mPendingParent);
+            mTransaction = null;
             mPendingParent = null;
             return sc;
         }
     }
 
-    private class HierarchyRecordingBuilderFactory implements SurfaceBuilderFactory {
+    private static class HierarchyRecordingBuilderFactory implements SurfaceBuilderFactory {
+        private LayerRecordingTransaction mTransaction;
+
+        HierarchyRecordingBuilderFactory(LayerRecordingTransaction transaction) {
+            mTransaction = transaction;
+        }
+
+        @Override
         public SurfaceControl.Builder make(SurfaceSession s) {
-            return new HierarchyRecorder(s);
+            final LayerRecordingTransaction transaction = mTransaction;
+            mTransaction = null;
+            return new HierarchyRecorder(s, transaction);
         }
     }
 
@@ -127,18 +151,17 @@
         // which is after construction of the DisplayContent, meaning the HierarchyRecorder
         // would miss construction of the top-level layers.
         mTransaction = new LayerRecordingTransaction();
-        sWm.mSurfaceBuilderFactory = new HierarchyRecordingBuilderFactory();
-        sWm.mTransactionFactory = () -> mTransaction;
+        mWm.mSurfaceBuilderFactory = new HierarchyRecordingBuilderFactory(mTransaction);
+        mWm.mTransactionFactory = () -> mTransaction;
     }
 
     @After
-    public void after() {
+    public void tearDown() {
         mTransaction.close();
-        mParentFor.keySet().forEach(SurfaceControl::destroy);
-        mParentFor.clear();
     }
 
-    LinkedList<SurfaceControl> getAncestors(LayerRecordingTransaction t, SurfaceControl sc) {
+    private static LinkedList<SurfaceControl> getAncestors(LayerRecordingTransaction t,
+            SurfaceControl sc) {
         LinkedList<SurfaceControl> p = new LinkedList<>();
         SurfaceControl current = sc;
         do {
@@ -148,23 +171,22 @@
             if (rs != null) {
                 current = rs;
             } else {
-                current = mParentFor.get(current);
+                current = t.getParentFor(current);
             }
         } while (current != null);
         return p;
     }
 
 
-    void assertZOrderGreaterThan(LayerRecordingTransaction t, SurfaceControl left,
+    private static void assertZOrderGreaterThan(LayerRecordingTransaction t, SurfaceControl left,
             SurfaceControl right) {
         final LinkedList<SurfaceControl> leftParentChain = getAncestors(t, left);
         final LinkedList<SurfaceControl> rightParentChain = getAncestors(t, right);
 
-        SurfaceControl commonAncestor = null;
         SurfaceControl leftTop = leftParentChain.peekLast();
         SurfaceControl rightTop = rightParentChain.peekLast();
         while (leftTop != null && rightTop != null && leftTop == rightTop) {
-            commonAncestor = leftParentChain.removeLast();
+            leftParentChain.removeLast();
             rightParentChain.removeLast();
             leftTop = leftParentChain.peekLast();
             rightTop = rightParentChain.peekLast();
@@ -189,7 +211,7 @@
 
     @Test
     public void testAssignWindowLayers_ForImeWithNoTarget() {
-        sWm.mInputMethodTarget = null;
+        mWm.mInputMethodTarget = null;
         mDisplayContent.assignChildLayers(mTransaction);
 
         // The Ime has an higher base layer than app windows and lower base layer than system
@@ -207,7 +229,7 @@
     @Test
     public void testAssignWindowLayers_ForImeWithAppTarget() {
         final WindowState imeAppTarget = createWindow("imeAppTarget");
-        sWm.mInputMethodTarget = imeAppTarget;
+        mWm.mInputMethodTarget = imeAppTarget;
 
         mDisplayContent.assignChildLayers(mTransaction);
 
@@ -233,7 +255,7 @@
                 TYPE_APPLICATION_MEDIA_OVERLAY, imeAppTarget.mToken,
                 "imeAppTargetChildBelowWindow");
 
-        sWm.mInputMethodTarget = imeAppTarget;
+        mWm.mInputMethodTarget = imeAppTarget;
         mDisplayContent.assignChildLayers(mTransaction);
 
         // Ime should be above all app windows except for child windows that are z-ordered above it
@@ -255,7 +277,7 @@
         final WindowState imeAppTarget = createWindow("imeAppTarget");
         final WindowState appAboveImeTarget = createWindow("appAboveImeTarget");
 
-        sWm.mInputMethodTarget = imeAppTarget;
+        mWm.mInputMethodTarget = imeAppTarget;
         mDisplayContent.assignChildLayers(mTransaction);
 
         // Ime should be above all app windows except for non-fullscreen app window above it and
@@ -278,7 +300,7 @@
                 mDisplayContent, "imeSystemOverlayTarget",
                 true /* ownerCanAddInternalSystemWindow */);
 
-        sWm.mInputMethodTarget = imeSystemOverlayTarget;
+        mWm.mInputMethodTarget = imeSystemOverlayTarget;
         mDisplayContent.assignChildLayers(mTransaction);
 
         // The IME target base layer is higher than all window except for the nav bar window, so the
@@ -301,7 +323,7 @@
 
     @Test
     public void testAssignWindowLayers_ForStatusBarImeTarget() {
-        sWm.mInputMethodTarget = mStatusBarWindow;
+        mWm.mInputMethodTarget = mStatusBarWindow;
         mDisplayContent.assignChildLayers(mTransaction);
 
         assertWindowHigher(mImeWindow, mChildAppWindowAbove);
@@ -322,8 +344,8 @@
         final WindowState dockedStackWindow = createWindowOnStack(null,
                 WINDOWING_MODE_SPLIT_SCREEN_PRIMARY, ACTIVITY_TYPE_STANDARD, TYPE_BASE_APPLICATION,
                 mDisplayContent, "dockedStackWindow");
-        final WindowState assistantStackWindow = createWindowOnStack(null, WINDOWING_MODE_FULLSCREEN,
-                ACTIVITY_TYPE_ASSISTANT, TYPE_BASE_APPLICATION,
+        final WindowState assistantStackWindow = createWindowOnStack(null,
+                WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_ASSISTANT, TYPE_BASE_APPLICATION,
                 mDisplayContent, "assistantStackWindow");
         final WindowState homeActivityWindow = createWindowOnStack(null, WINDOWING_MODE_FULLSCREEN,
                 ACTIVITY_TYPE_HOME, TYPE_BASE_APPLICATION,
@@ -368,7 +390,8 @@
         final WindowState anyWindow = createWindow("anyWindow");
         final WindowState child = createWindow(anyWindow, TYPE_APPLICATION_MEDIA, mDisplayContent,
                 "TypeApplicationMediaChild");
-        final WindowState mediaOverlayChild = createWindow(anyWindow, TYPE_APPLICATION_MEDIA_OVERLAY,
+        final WindowState mediaOverlayChild = createWindow(anyWindow,
+                TYPE_APPLICATION_MEDIA_OVERLAY,
                 mDisplayContent, "TypeApplicationMediaOverlayChild");
 
         mDisplayContent.assignChildLayers(mTransaction);
@@ -388,8 +411,8 @@
         final WindowState splitScreenSecondaryWindow = createWindowOnStack(null,
                 WINDOWING_MODE_SPLIT_SCREEN_SECONDARY, ACTIVITY_TYPE_STANDARD,
                 TYPE_BASE_APPLICATION, mDisplayContent, "splitScreenSecondaryWindow");
-        final WindowState assistantStackWindow = createWindowOnStack(null, WINDOWING_MODE_FULLSCREEN,
-                ACTIVITY_TYPE_ASSISTANT, TYPE_BASE_APPLICATION,
+        final WindowState assistantStackWindow = createWindowOnStack(null,
+                WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_ASSISTANT, TYPE_BASE_APPLICATION,
                 mDisplayContent, "assistantStackWindow");
 
         mDisplayContent.assignChildLayers(mTransaction);