cc: Pass Occlusion instead of OcclusionTracker to LayerImpls

cc/layers/heads_up_display_layer_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_LAYERS_HEADS_UP_DISPLAY_LAYER_IMPL_H_
 #define CC_LAYERS_HEADS_UP_DISPLAY_LAYER_IMPL_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 22 matching lines @@
     return make_scoped_ptr(new HeadsUpDisplayLayerImpl(tree_impl, id));
   }
   virtual ~HeadsUpDisplayLayerImpl();
 
   virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl)
       override;
 
   virtual bool WillDraw(DrawMode draw_mode,
                         ResourceProvider* resource_provider) override;
   virtual void AppendQuads(RenderPass* render_pass,
-                           const OcclusionTracker<LayerImpl>& occlusion_tracker,
+                           const Occlusion& occlusion_in_content_space,
                            AppendQuadsData* append_quads_data) override;
   void UpdateHudTexture(DrawMode draw_mode,
                         ResourceProvider* resource_provider);
 
   virtual void ReleaseResources() override;
 
   bool IsAnimatingHUDContents() const { return fade_step_ > 0; }
 
  private:
   class Graph {
@@ skipping 80 matching lines @@
   std::vector<DebugRect> paint_rects_;
 
   base::TimeTicks time_of_last_graph_update_;
 
   DISALLOW_COPY_AND_ASSIGN(HeadsUpDisplayLayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_HEADS_UP_DISPLAY_LAYER_IMPL_H_