cc : Fix effect tree index bug in cc::LayerImpl::Opacity

cc/layers/layer_impl.cc

 // Copyright 2012 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/layer_impl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 915 matching lines @@
 }
 
 void LayerImpl::SetContentsOpaque(bool opaque) {
   if (contents_opaque_ == opaque)
     return;
 
   contents_opaque_ = opaque;
 }
 
 float LayerImpl::Opacity() const {
-  if (!layer_tree_impl()->property_trees()->IsInIdToIndexMap(
-          PropertyTrees::TreeType::EFFECT, id()))
+  PropertyTrees* property_trees = layer_tree_impl()->property_trees();
+  if (!property_trees->IsInIdToIndexMap(PropertyTrees::TreeType::EFFECT, id()))
     return 1.f;
-  EffectNode* node =
-      layer_tree_impl()->property_trees()->effect_tree.Node(effect_tree_index_);
+  EffectNode* node = property_trees->effect_tree.Node(
+      property_trees->effect_id_to_index_map[id()]);
   return node->data.opacity;
 }
 
 bool LayerImpl::OpacityIsAnimating() const {
   return layer_tree_impl_->IsAnimatingOpacityProperty(this);
 }
 
 bool LayerImpl::HasPotentiallyRunningOpacityAnimation() const {
   return layer_tree_impl_->HasPotentiallyRunningOpacityAnimation(this);
 }
@@ skipping 390 matching lines @@
            .layer_transforms_should_scale_layer_contents) {
     return default_scale;
   }
 
   gfx::Vector2dF transform_scales = MathUtil::ComputeTransform2dScaleComponents(
       ScreenSpaceTransform(), default_scale);
   return std::max(transform_scales.x(), transform_scales.y());
 }
 
 }  // namespace cc