Fix cc scrollbar layer issues with initialization, and use element ids throughout.

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 <memory>
@@ skipping 629 matching lines @@
   // These maps allow mapping directly from a compositor element id to the
   // respective property node. This will eventually allow simplifying logic in
   // various places that today has to map from element id to layer id, and then
   // from layer id to the respective property node. Completing that work is
   // pending the launch of Slimming Paint v2 and reworking UI compositor logic
   // to produce cc property trees and these maps.
   base::flat_map<ElementId, int> element_id_to_effect_node_index;
   base::flat_map<ElementId, int> element_id_to_scroll_node_index;
   base::flat_map<ElementId, int> element_id_to_transform_node_index;
 
-  std::vector<int> always_use_active_tree_opacity_effect_ids;
   TransformTree transform_tree;
   EffectTree effect_tree;
   ClipTree clip_tree;
   ScrollTree scroll_tree;
   bool needs_rebuild;
   bool can_adjust_raster_scales;
   // Change tracking done on property trees needs to be preserved across commits
   // (when they are not rebuild). We cache a global bool which stores whether
   // we did any change tracking so that we can skip copying the change status
   // between property trees when this bool is false.
   bool changed;
   // We cache a global bool for full tree damages to avoid walking the entire
   // tree.
   // TODO(jaydasika): Changes to transform and effects that damage the entire
   // tree should be tracked by this bool. Currently, they are tracked by the
   // individual nodes.
   bool full_tree_damaged;
   int sequence_number;
   bool is_main_thread;
   bool is_active;
 
   void clear();
 
   void SetInnerViewportContainerBoundsDelta(gfx::Vector2dF bounds_delta);
   void SetOuterViewportContainerBoundsDelta(gfx::Vector2dF bounds_delta);
   void SetInnerViewportScrollBoundsDelta(gfx::Vector2dF bounds_delta);
-  void PushOpacityIfNeeded(PropertyTrees* target_tree);
   void RemoveIdFromIdToIndexMaps(int id);
   void UpdateChangeTracking();
   void PushChangeTrackingTo(PropertyTrees* tree);
   void ResetAllChangeTracking();
 
   gfx::Vector2dF inner_viewport_container_bounds_delta() const {
     return inner_viewport_container_bounds_delta_;
   }
 
   gfx::Vector2dF outer_viewport_container_bounds_delta() const {
@@ skipping 36 matching lines @@
   DrawTransforms& GetDrawTransforms(int transform_id, int effect_id) const;
   DrawTransformData& FetchDrawTransformsDataFromCache(int transform_id,
                                                       int effect_id) const;
 
   PropertyTreesCachedData cached_data_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_PROPERTY_TREE_H_