Support for drawing a debug border around animated layers

cc/layers/layer_impl.h

Index: cc/layers/layer_impl.h
diff --git a/cc/layers/layer_impl.h b/cc/layers/layer_impl.h
index 13e2876880f134cb1241d599430585b93b9c0dee..c8514ef8e931a72c3fc28bb17bd4eac4a53bcaa1 100644
--- a/cc/layers/layer_impl.h
+++ b/cc/layers/layer_impl.h
@@ -362,6 +362,12 @@ class CC_EXPORT LayerImpl : public LayerAnimationValueObserver,
   float contents_scale_y() const { return draw_properties_.contents_scale_y; }
   void SetContentsScale(float contents_scale_x, float contents_scale_y);
 
+  // Computes a box in screen space that should entirely contain the layer's
+  // bounds through the entirety of the layer's current animation. Returns true
+  // and sets |out| to the inflation if there are animations that can inflate
+  // bounds in the path to the root layer. Returns false otherwise.
+  bool GetAnimationBounds(gfx::BoxF* out) const { return false; }
+
   virtual void CalculateContentsScale(float ideal_contents_scale,
                                       float device_scale_factor,
                                       float page_scale_factor,