cc: Directly use property trees to calculate clip rect

cc/trees/property_tree.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_TREES_PROPERTY_TREE_H_
 #define CC_TREES_PROPERTY_TREE_H_
 
 #include <stddef.h>
 
 #include <unordered_map>
@@ skipping 251 matching lines @@
 
   bool has_render_surface;
   bool has_copy_request;
   bool has_background_filters;
   bool is_drawn;
   bool has_animated_opacity;
   // We need to track changes to effects on the compositor to compute damage
   // 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;
 
   void ToProtobuf(proto::TreeNode* proto) const;
   void FromProtobuf(const proto::TreeNode& proto);
 };
 
 typedef TreeNode<EffectNodeData> EffectNode;
 
 struct CC_EXPORT ScrollNodeData {
@@ skipping 98 matching lines @@
   // relationship. Transforms between other pairs of nodes may only be computed
   // if the following condition holds: let id1 the larger id and let id2 be the
   // other id; then the nearest ancestor of node id1 whose id is smaller than
   // id2 is the lowest common ancestor of the pair of nodes, and the transform
   // from this lowest common ancestor to node id2 is only a 2d translation.
   bool ComputeTransform(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| 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).
   bool ComputeTransformWithDestinationSublayerScale(
       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 |source_id|.  The function returns false
@@ skipping 250 matching lines @@
 
  private:
   gfx::Vector2dF inner_viewport_container_bounds_delta_;
   gfx::Vector2dF outer_viewport_container_bounds_delta_;
   gfx::Vector2dF inner_viewport_scroll_bounds_delta_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_PROPERTY_TREE_H_