cc: Directly use property trees to calculate clip rect

cc/trees/draw_property_utils.h

Index: cc/trees/draw_property_utils.h
diff --git a/cc/trees/draw_property_utils.h b/cc/trees/draw_property_utils.h
index 70bd8a00824456f76ca0b1e8a1b33a277919ca65..6457a058acce4e658675e4cc2186ac1d55356b0e 100644
--- a/cc/trees/draw_property_utils.h
+++ b/cc/trees/draw_property_utils.h
@@ -91,6 +91,9 @@ void CC_EXPORT ComputeLayerDrawProperties(LayerImpl* layer,
 void CC_EXPORT ComputeSurfaceDrawProperties(const PropertyTrees* property_trees,
                                             RenderSurfaceImpl* render_surface);
 
+void CC_EXPORT VerifyClipTreeCalculations(const LayerImplList& layer_list,
+                                          PropertyTrees* property_trees);
+
 gfx::Transform CC_EXPORT DrawTransform(const Layer* layer,
                                        const TransformTree& tree);