Clarify property tree id-to-index map names.

cc/layers/render_surface_impl.cc

 // Copyright 2011 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/layers/render_surface_impl.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 
@@ skipping 144 matching lines @@
   return owning_layer_->transform_tree_index();
 }
 
 int RenderSurfaceImpl::ClipTreeIndex() const {
   return owning_layer_->clip_tree_index();
 }
 
 int RenderSurfaceImpl::EffectTreeIndex() const {
   DCHECK_EQ(effect_tree_index_,
             layer_tree_impl_->property_trees()
-                ->effect_id_to_index_map[stable_effect_id_]);
+                ->layer_id_to_effect_node_index[stable_effect_id_]);
   return effect_tree_index_;
 }
 
 const EffectNode* RenderSurfaceImpl::OwningEffectNode() const {
   return layer_tree_impl_->property_trees()->effect_tree.Node(
       EffectTreeIndex());
 }
 
 void RenderSurfaceImpl::SetClipRect(const gfx::Rect& clip_rect) {
   if (clip_rect == draw_properties_.clip_rect)
@@ skipping 237 matching lines @@
 
   RenderPassDrawQuad* quad =
       render_pass->CreateAndAppendDrawQuad<RenderPassDrawQuad>();
   quad->SetNew(shared_quad_state, content_rect(), visible_layer_rect,
                GetRenderPassId(), mask_resource_id, mask_uv_scale,
                mask_texture_size, owning_layer_to_target_scale,
                FiltersOrigin());
 }
 
 }  // namespace cc