Report wallpaper offset to the wallpaper, use this in the image wallpaper.
Wallpapers can now be just the size of the screen, and get told when their
scroll position should change to do the updating on their own.
diff --git a/core/java/android/view/IWindow.aidl b/core/java/android/view/IWindow.aidl
index 99d5c0c..ec2036e 100644
--- a/core/java/android/view/IWindow.aidl
+++ b/core/java/android/view/IWindow.aidl
@@ -56,4 +56,9 @@
* to date on the current state showing navigational focus (touch mode) too.
*/
void windowFocusChanged(boolean hasFocus, boolean inTouchMode);
+
+ /**
+ * Called for wallpaper windows when their offsets change.
+ */
+ void dispatchWallpaperOffsets(float x, float y);
}