Stop painting when receiving delegated frame

ui/compositor/layer.h

Index: ui/compositor/layer.h
diff --git a/ui/compositor/layer.h b/ui/compositor/layer.h
index 6af9cd766abe662107f5e2f6a85908458cf779bf..d9c1e809b0bdeba989960f6830ddc1ef567c5166 100644
--- a/ui/compositor/layer.h
+++ b/ui/compositor/layer.h
@@ -318,6 +318,10 @@ class COMPOSITOR_EXPORT Layer
   // Notifies the layer that the device scale factor has changed.
   void OnDeviceScaleFactorChanged(float device_scale_factor);
 
+  // Notifies the layer that one of its children has received a new
+  // delegated frame.
+  void OnDelegatedFrameDamage(const gfx::Rect &damage_rect_in_dip);
+
   // Requets a copy of the layer's output as a texture or bitmap.
   void RequestCopyOfOutput(scoped_ptr<cc::CopyOutputRequest> request);