cc: Compute RenderSurfaceImpl's TransformTreeIndex using its effect node

cc/trees/draw_property_utils.cc

 // 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.
 
 #include "cc/trees/draw_property_utils.h"
 
 #include <stddef.h>
 
 #include <vector>
 
@@ skipping 1260 matching lines @@
 
 static void SetSurfaceDrawTransform(const PropertyTrees* property_trees,
                                     RenderSurfaceImpl* render_surface) {
   const TransformTree& transform_tree = property_trees->transform_tree;
   const EffectTree& effect_tree = property_trees->effect_tree;
   const TransformNode* transform_node =
       transform_tree.Node(render_surface->TransformTreeIndex());
   const EffectNode* effect_node =
       effect_tree.Node(render_surface->EffectTreeIndex());
   // The draw transform of root render surface is identity tranform.
-  if (transform_node->id == 1) {
+  if (transform_node->id == TransformTree::kRootNodeId) {
     render_surface->SetDrawTransform(gfx::Transform());
     return;
   }
 
   gfx::Transform render_surface_transform;
   const EffectNode* target_effect_node =
       effect_tree.Node(effect_node->target_id);
   property_trees->GetToTarget(transform_node->id, target_effect_node->id,
                               &render_surface_transform);
 
@@ skipping 264 matching lines @@
 void UpdateElasticOverscroll(PropertyTrees* property_trees,
                              const Layer* overscroll_elasticity_layer,
                              const gfx::Vector2dF& elastic_overscroll) {
   UpdateElasticOverscrollInternal(property_trees, overscroll_elasticity_layer,
                                   elastic_overscroll);
 }
 
 }  // namespace draw_property_utils
 
 }  // namespace cc