Change cc::ElementId to be a uint64_t

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 499 matching lines @@
   LocalSurfaceId local_surface_id_;
 
   scoped_refptr<SyncedElasticOverscroll> elastic_overscroll_;
 
   std::unique_ptr<OwnedLayerImplList> layers_;
   LayerImplMap layer_id_map_;
   LayerImplList layer_list_;
   // Set of layers that need to push properties.
   std::unordered_set<LayerImpl*> layers_that_should_push_properties_;
 
-  std::unordered_map<ElementId, int, ElementIdHash> element_layers_map_;
+  std::unordered_map<ElementId, int> element_layers_map_;
 
-  std::unordered_map<ElementId, float, ElementIdHash>
-      element_id_to_opacity_animations_;
-  std::unordered_map<ElementId, gfx::Transform, ElementIdHash>
+  std::unordered_map<ElementId, float> element_id_to_opacity_animations_;
+  std::unordered_map<ElementId, gfx::Transform>
       element_id_to_transform_animations_;
-  std::unordered_map<ElementId, FilterOperations, ElementIdHash>
+  std::unordered_map<ElementId, FilterOperations>
       element_id_to_filter_animations_;
 
   // 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 element ids to scrollbar layer ids. For each scroll layer,
   // there may be 1 or 2 scrollbar layers (for vertical and horizontal). (This
   // is derived from ScrollbarLayerImplBase::scroll_element_id_ and exists to
@@ skipping 45 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_