Use element id's for animations

cc/trees/layer_tree_impl.h

 // 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.
 
 #ifndef CC_TREES_LAYER_TREE_IMPL_H_
 #define CC_TREES_LAYER_TREE_IMPL_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 135 matching lines @@
 
   void PushPropertiesTo(LayerTreeImpl* tree_impl);
 
   void MoveChangeTrackingToLayers();
 
   LayerListIterator<LayerImpl> begin();
   LayerListIterator<LayerImpl> end();
   LayerListReverseIterator<LayerImpl> rbegin();
   LayerListReverseIterator<LayerImpl> rend();
 
-  struct CC_EXPORT ElementLayers {
-    // Transform and opacity mutations apply to this layer.
-    LayerImpl* main = nullptr;
-    // Scroll mutations apply to this layer.
-    LayerImpl* scroll = nullptr;
-  };
-
-  void AddToElementMap(LayerImpl* layer);
-  void RemoveFromElementMap(LayerImpl* layer);
-
   void AddToOpacityAnimationsMap(int id, float opacity);
 
-  ElementLayers GetMutableLayers(uint64_t element_id);
   int source_frame_number() const { return source_frame_number_; }
   void set_source_frame_number(int frame_number) {
     source_frame_number_ = frame_number;
   }
 
   bool is_first_frame_after_commit() const {
     return source_frame_number_ != is_first_frame_after_commit_tracker_;
   }
 
   void set_is_first_frame_after_commit(bool is_first_frame_after_commit) {
@@ skipping 77 matching lines @@
     return elastic_overscroll_.get();
   }
 
   SyncedTopControls* top_controls_shown_ratio() {
     return top_controls_shown_ratio_.get();
   }
   const SyncedTopControls* top_controls_shown_ratio() const {
     return top_controls_shown_ratio_.get();
   }
 
+  void SetElementIdsForTesting();
+
   // Updates draw properties and render surface layer list, as well as tile
   // priorities. Returns false if it was unable to update.  Updating lcd
   // text may cause invalidations, so should only be done after a commit.
   bool UpdateDrawProperties(bool update_lcd_text);
   void BuildPropertyTreesForTesting();
 
   void set_needs_update_draw_properties() {
     needs_update_draw_properties_ = true;
   }
   bool needs_update_draw_properties() const {
@@ skipping 17 matching lines @@
 
   // These return the size of the root scrollable area and the size of
   // the user-visible scrolling viewport, in CSS layout coordinates.
   gfx::SizeF ScrollableSize() const;
   gfx::SizeF ScrollableViewportSize() const;
 
   gfx::Rect RootScrollLayerDeviceViewportBounds() const;
 
   LayerImpl* LayerById(int id) const;
 
+  // TODO(vollick): this is deprecated. It is used by
+  // animation/compositor-worker to look up layers to mutate, but in future, we
+  // will update property trees.
+  LayerImpl* LayerByElementId(ElementId element_id) const;
+  void AddToElementMap(LayerImpl* layer);
+  void RemoveFromElementMap(LayerImpl* layer);
+
   void AddLayerShouldPushProperties(LayerImpl* layer);
   void RemoveLayerShouldPushProperties(LayerImpl* layer);
   std::unordered_set<LayerImpl*>& LayersThatShouldPushProperties();
   bool LayerNeedsPushPropertiesForTesting(LayerImpl* layer);
 
   // These should be called by LayerImpl's ctor/dtor.
   void RegisterLayer(LayerImpl* layer);
   void UnregisterLayer(LayerImpl* layer);
 
   // These manage ownership of the LayerImpl.
@@ skipping 196 matching lines @@
   float device_scale_factor_;
   float painted_device_scale_factor_;
 
   scoped_refptr<SyncedElasticOverscroll> elastic_overscroll_;
 
   std::unique_ptr<OwnedLayerImplList> layers_;
   LayerImplMap layer_id_map_;
   // Set of layers that need to push properties.
   std::unordered_set<LayerImpl*> layers_that_should_push_properties_;
 
-  std::unordered_map<uint64_t, ElementLayers> element_layers_map_;
+  std::unordered_map<ElementId, LayerImpl*, ElementIdHash> element_layers_map_;
 
   std::unordered_map<int, float> opacity_animations_map_;
 
   // Maps from clip layer ids to scroll layer ids.  Note that this only includes
   // the subset of clip layers that act as scrolling containers.  (This is
   // derived from LayerImpl::scroll_clip_layer_ and exists to avoid O(n) walks.)
   std::unordered_map<int, int> clip_scroll_map_;
 
   // Maps scroll layer ids to scrollbar layer ids.  For each scroll layer, there
   // may be 1 or 2 scrollbar layers (for vertical and horizontal).  (This is
@@ skipping 41 matching lines @@
 
   std::unique_ptr<PendingPageScaleAnimation> pending_page_scale_animation_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(LayerTreeImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_IMPL_H_