cc: Directly use property trees to calculate clip rect

cc/trees/property_tree.h

Index: cc/trees/property_tree.h
diff --git a/cc/trees/property_tree.h b/cc/trees/property_tree.h
index 64226fdbb8d902ab2b0288621421223b73590307..125667cfc5428fda6835f9f75a56e517be5f4c96 100644
--- a/cc/trees/property_tree.h
+++ b/cc/trees/property_tree.h
@@ -269,8 +269,11 @@ struct CC_EXPORT EffectNodeData {
   // rect.
   bool effect_changed;
   int num_copy_requests_in_subtree;
+  bool has_unclipped_descendants;
   int transform_id;
   int clip_id;
+  int target_id;
+  gfx::Rect clip_rect;
 
   bool operator==(const EffectNodeData& other) const;
 
@@ -389,6 +392,15 @@ class CC_EXPORT TransformTree final : public PropertyTree<TransformNode> {
                         gfx::Transform* transform) const;
 
   // Computes the change of basis transform from node |source_id| to |dest_id|,
+  // including any sublayer scale at |dest_id| but not including sublayer scale
+  // at |source_id|. The function returns false iff the inverse of a singular
+  // transform was used (and the result should, therefore, not be trusted).
+  bool ComputeTransformWithDifferenceInSublayerScale(

[ajuma, 2016/03/15 14:59:56]

Seems unused?

[weiliangc, 2016/03/15 15:29:36]

Ah thanks for the catch. Removed.

+      int source_id,
+      int dest_id,
+      gfx::Transform* transform) const;
+
+  // Computes the change of basis transform from node |source_id| to |dest_id|,
   // including any sublayer scale at |dest_id|.  The function returns false iff
   // the inverse of a singular transform was used (and the result should,
   // therefore, not be trusted).