DO NOT MERGE Do not call drawableChanged pre Q

am: 843f9dee8b

Change-Id: Id54fa3b2327faec88c936228109643c8425eeb2a

core/java/android/view/View.java

@@ -967,6 +967,19 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
      */
     static boolean sBrokenInsetsDispatch;
 
+    /**
+     * Prior to Q, calling
+     * {@link com.android.internal.policy.DecorView#setBackgroundDrawable(Drawable)}
+     * did not call update the window format so the opacity of the background was not correctly
+     * applied to the window. Some applications rely on this misbehavior to work properly.
+     * <p>
+     * From Q, {@link com.android.internal.policy.DecorView#setBackgroundDrawable(Drawable)} is
+     * the same as {@link com.android.internal.policy.DecorView#setWindowBackground(Drawable)}
+     * which updates the window format.
+     * @hide
+     */
+    protected static boolean sBrokenWindowBackground;
+
     /** @hide */
     @IntDef({NOT_FOCUSABLE, FOCUSABLE, FOCUSABLE_AUTO})
     @Retention(RetentionPolicy.SOURCE)
@@ -5104,6 +5117,8 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
             sBrokenInsetsDispatch = ViewRootImpl.sNewInsetsMode != NEW_INSETS_MODE_FULL
                     || targetSdkVersion < Build.VERSION_CODES.Q;
 
+            sBrokenWindowBackground = targetSdkVersion < Build.VERSION_CODES.Q;
+
             sCompatibilityDone = true;
         }
     }

core/java/com/android/internal/policy/DecorView.java

@@ -983,13 +983,14 @@ public class DecorView extends FrameLayout implements RootViewSurfaceTaker, Wind
 
     @Override
     public void setBackgroundDrawable(Drawable background) {
-
         // TODO: This should route through setWindowBackground, but late in the release to make this
         // change.
         if (mOriginalBackgroundDrawable != background) {
             mOriginalBackgroundDrawable = background;
             updateBackgroundDrawable();
-            drawableChanged();
+            if (!View.sBrokenWindowBackground) {
+                drawableChanged();
+            }
         }
     }