Support for drawing a debug border around animated layers

cc/debug/debug_rect_history.h

Index: cc/debug/debug_rect_history.h
diff --git a/cc/debug/debug_rect_history.h b/cc/debug/debug_rect_history.h
index 346148a93fc308d7bb96e6aba77f49e495f907b4..0dae431bd5f977330723458eebdce3c945bf748f 100644
--- a/cc/debug/debug_rect_history.h
+++ b/cc/debug/debug_rect_history.h
@@ -53,6 +53,7 @@ enum DebugRectType {
   TOUCH_EVENT_HANDLER_RECT_TYPE,
   WHEEL_EVENT_HANDLER_RECT_TYPE,
   NON_FAST_SCROLLABLE_RECT_TYPE,
+  ANIMATION_BOUNDS_RECT_TYPE,
 };
 
 struct DebugRect {
@@ -103,6 +104,8 @@ class DebugRectHistory {
   void SaveWheelEventHandlerRectsCallback(LayerImpl* layer);
   void SaveNonFastScrollableRects(LayerImpl* layer);
   void SaveNonFastScrollableRectsCallback(LayerImpl* layer);
+  void SaveLayerAnimationBoundsRects(
+      const LayerImplList& render_surface_layer_list);
 
   std::vector<DebugRect> debug_rects_;