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
diff --git a/core/java/android/view/IWallpaperVisibilityListener.aidl b/core/java/android/view/IWallpaperVisibilityListener.aidl
new file mode 100644
index 0000000..349f984
--- /dev/null
+++ b/core/java/android/view/IWallpaperVisibilityListener.aidl
@@ -0,0 +1,30 @@
+/*
+ * 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 android.view;
+
+/**
+ * Listener to be invoked when wallpaper visibility changes.
+ * {@hide}
+ */
+oneway interface IWallpaperVisibilityListener {
+    /**
+     * Method that will be invoked when wallpaper becomes visible or hidden.
+     * @param visible True if wallpaper is being displayed; false otherwise.
+     * @param displayId The id of the display where wallpaper visibility changed.
+     */
+    void onWallpaperVisibilityChanged(boolean visible, int displayId);
+}