Scrims should be grey when in-app

Bug: 38164389
Test: runtest -x colorextraction/tests/src/com/google/android/colorextraction/ColorExtractorTest.java
Test: runtest -x tests/src/com/android/systemui/colorextraction/SysuiColorExtractorTests.java
Change-Id: Ifcc04a8562e46b4f65bce0470ccd6c02dffcf377
(cherry picked from commit e1571705e6ea8367e7ee93d61104ce27035492dc)
diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index 54983c8..fbe6f94 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -210,6 +210,7 @@
     final DisplayMetrics mRealDisplayMetrics = new DisplayMetrics();
     /** @see #computeCompatSmallestWidth(boolean, int, int, int, int) */
     private final DisplayMetrics mTmpDisplayMetrics = new DisplayMetrics();
+
     /**
      * Compat metrics computed based on {@link #mDisplayMetrics}.
      * @see #updateDisplayAndOrientation(int)
@@ -226,6 +227,7 @@
      * @see #updateRotationUnchecked(boolean)
      */
     private int mRotation = 0;
+
     /**
      * Last applied orientation of the display.
      * Constants as per {@link android.content.pm.ActivityInfo.ScreenOrientation}.
@@ -233,6 +235,7 @@
      * @see WindowManagerService#updateOrientationFromAppTokensLocked(boolean, int)
      */
     private int mLastOrientation = SCREEN_ORIENTATION_UNSPECIFIED;
+
     /**
      * Flag indicating that the application is receiving an orientation that has different metrics
      * than it expected. E.g. Portrait instead of Landscape.
@@ -240,6 +243,7 @@
      * @see #updateRotationUnchecked(boolean)
      */
     private boolean mAltOrientation = false;
+
     /**
      * Orientation forced by some window. If there is no visible window that specifies orientation
      * it is set to {@link android.content.pm.ActivityInfo#SCREEN_ORIENTATION_UNSPECIFIED}.
@@ -247,6 +251,7 @@
      * @see NonAppWindowContainers#getOrientation()
      */
     private int mLastWindowForcedOrientation = SCREEN_ORIENTATION_UNSPECIFIED;
+
     /**
      * Last orientation forced by the keyguard. It is applied when keyguard is shown and is not
      * occluded.
@@ -255,6 +260,11 @@
      */
     private int mLastKeyguardForcedOrientation = SCREEN_ORIENTATION_UNSPECIFIED;
 
+    /**
+     * Keep track of wallpaper visibility to notify changes.
+     */
+    private boolean mLastWallpaperVisible = false;
+
     private Rect mBaseDisplayRect = new Rect();
     private Rect mContentRect = new Rect();
 
@@ -2765,6 +2775,12 @@
 
         stopDimmingIfNeeded();
 
+        final boolean wallpaperVisible = mWallpaperController.isWallpaperVisible();
+        if (wallpaperVisible != mLastWallpaperVisible) {
+            mLastWallpaperVisible = wallpaperVisible;
+            mService.mWallpaperVisibilityListeners.notifyWallpaperVisibilityChanged(this);
+        }
+
         while (!mTmpUpdateAllDrawn.isEmpty()) {
             final AppWindowToken atoken = mTmpUpdateAllDrawn.removeLast();
             // See if any windows have been drawn, so they (and others associated with them)
diff --git a/services/core/java/com/android/server/wm/WallpaperVisibilityListeners.java b/services/core/java/com/android/server/wm/WallpaperVisibilityListeners.java
new file mode 100644
index 0000000..2c06851
--- /dev/null
+++ b/services/core/java/com/android/server/wm/WallpaperVisibilityListeners.java
@@ -0,0 +1,79 @@
+/*
+ * 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 android.os.RemoteCallbackList;
+import android.os.RemoteException;
+import android.util.SparseArray;
+import android.view.IWallpaperVisibilityListener;
+
+/**
+ * Manages and trigger wallpaper visibility listeners.
+ */
+class WallpaperVisibilityListeners {
+
+    /**
+     * A map of displayIds and its listeners.
+     */
+    private final SparseArray<RemoteCallbackList<IWallpaperVisibilityListener>> mDisplayListeners =
+            new SparseArray<>();
+
+    void registerWallpaperVisibilityListener(IWallpaperVisibilityListener listener,
+            int displayId) {
+        RemoteCallbackList<IWallpaperVisibilityListener> listeners =
+                mDisplayListeners.get(displayId);
+        if (listeners == null) {
+            listeners = new RemoteCallbackList<>();
+            mDisplayListeners.append(displayId, listeners);
+        }
+        listeners.register(listener);
+    }
+
+    void unregisterWallpaperVisibilityListener(IWallpaperVisibilityListener listener,
+            int displayId) {
+        RemoteCallbackList<IWallpaperVisibilityListener> listeners =
+                mDisplayListeners.get(displayId);
+        if (listeners == null) {
+            return;
+        }
+        listeners.unregister(listener);
+    }
+
+    void notifyWallpaperVisibilityChanged(DisplayContent displayContent) {
+        final int displayId = displayContent.getDisplayId();
+        final boolean visible = displayContent.mWallpaperController.isWallpaperVisible();
+        RemoteCallbackList<IWallpaperVisibilityListener> displayListeners =
+                mDisplayListeners.get(displayId);
+
+        // No listeners for this display.
+        if (displayListeners == null) {
+            return;
+        }
+
+        int i = displayListeners.beginBroadcast();
+        while (i > 0) {
+            i--;
+            IWallpaperVisibilityListener listener = displayListeners.getBroadcastItem(i);
+            try {
+                listener.onWallpaperVisibilityChanged(visible, displayId);
+            } catch (RemoteException e) {
+                // Nothing to do in here, RemoteCallbackListener will clean it up.
+            }
+        }
+        displayListeners.finishBroadcast();
+    }
+}
diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/android/server/wm/WindowManagerService.java
index 41ddf0c..93116a3 100644
--- a/services/core/java/com/android/server/wm/WindowManagerService.java
+++ b/services/core/java/com/android/server/wm/WindowManagerService.java
@@ -181,6 +181,7 @@
 import android.view.IOnKeyguardExitResult;
 import android.view.IPinnedStackListener;
 import android.view.IRotationWatcher;
+import android.view.IWallpaperVisibilityListener;
 import android.view.IWindow;
 import android.view.IWindowId;
 import android.view.IWindowManager;
@@ -549,9 +550,9 @@
     }
 
     class RotationWatcher {
-        IRotationWatcher mWatcher;
-        IBinder.DeathRecipient mDeathRecipient;
-        int mDisplayId;
+        final IRotationWatcher mWatcher;
+        final IBinder.DeathRecipient mDeathRecipient;
+        final int mDisplayId;
         RotationWatcher(IRotationWatcher watcher, IBinder.DeathRecipient deathRecipient,
                 int displayId) {
             mWatcher = watcher;
@@ -562,6 +563,8 @@
 
     ArrayList<RotationWatcher> mRotationWatchers = new ArrayList<>();
     int mDeferredRotationPauseCount;
+    final WallpaperVisibilityListeners mWallpaperVisibilityListeners =
+            new WallpaperVisibilityListeners();
 
     int mSystemDecorLayer = 0;
     final Rect mScreenRect = new Rect();
@@ -3937,6 +3940,29 @@
         }
     }
 
+    @Override
+    public boolean registerWallpaperVisibilityListener(IWallpaperVisibilityListener listener,
+            int displayId) {
+        synchronized (mWindowMap) {
+            final DisplayContent displayContent = mRoot.getDisplayContentOrCreate(displayId);
+            if (displayContent == null) {
+                throw new IllegalArgumentException("Trying to register visibility event "
+                        + "for invalid display: " + displayId);
+            }
+            mWallpaperVisibilityListeners.registerWallpaperVisibilityListener(listener, displayId);
+            return displayContent.mWallpaperController.isWallpaperVisible();
+        }
+    }
+
+    @Override
+    public void unregisterWallpaperVisibilityListener(IWallpaperVisibilityListener listener,
+            int displayId) {
+        synchronized (mWindowMap) {
+            mWallpaperVisibilityListeners
+                    .unregisterWallpaperVisibilityListener(listener, displayId);
+        }
+    }
+
     /**
      * Apps that use the compact menu panel (as controlled by the panelMenuIsCompact
      * theme attribute) on devices that feature a physical options menu key attempt to position