Migrate frameworks/base/services/tests/servicestests to androidx.test

See go/jetpack-test-android-migration

cherrypicked from ag/4608401

Test: atest FrameworksServicesTests
Change-Id: I2d9641c681489135aa3167bb4c9b1296a1a6a4f7
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 649de4a..c9d8004 100644
--- a/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotCacheTest.java
+++ b/services/tests/servicestests/src/com/android/server/wm/TaskSnapshotCacheTest.java
@@ -17,12 +17,14 @@
 package com.android.server.wm;
 
 import static android.view.WindowManager.LayoutParams.FIRST_APPLICATION_WINDOW;
+
 import static junit.framework.Assert.assertNotNull;
 import static junit.framework.Assert.assertNull;
 
 import android.platform.test.annotations.Presubmit;
-import android.support.test.filters.SmallTest;
-import android.support.test.runner.AndroidJUnit4;
+
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Before;
 import org.junit.Test;