Re-land: cc: Use worker context for one-copy tile initialization.

cc/trees/layer_tree_host_impl.h

 // Copyright 2011 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_HOST_IMPL_H_
 #define CC_TREES_LAYER_TREE_HOST_IMPL_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 534 matching lines @@
   // ReadyToDraw. crbug.com/469175
   void SetRequiresHighResToDraw() { requires_high_res_to_draw_ = true; }
   void ResetRequiresHighResToDraw() { requires_high_res_to_draw_ = false; }
   bool RequiresHighResToDraw() const { return requires_high_res_to_draw_; }
 
   // Only valid for synchronous (non-scheduled) single-threaded case.
   void SynchronouslyInitializeAllTiles();
 
   virtual void CreateResourceAndTileTaskWorkerPool(
       scoped_ptr<TileTaskWorkerPool>* tile_task_worker_pool,
-      scoped_ptr<ResourcePool>* resource_pool,
-      scoped_ptr<ResourcePool>* staging_resource_pool);
+      scoped_ptr<ResourcePool>* resource_pool);
 
   bool prepare_tiles_needed() const { return tile_priorities_dirty_; }
 
   FrameTimingTracker* frame_timing_tracker() {
     return frame_timing_tracker_.get();
   }
 
   gfx::Vector2dF ScrollLayer(LayerImpl* layer_impl,
                              const gfx::Vector2dF& delta,
                              const gfx::Point& viewport_point,
@@ skipping 132 matching lines @@
 
   scoped_ptr<ResourceProvider> resource_provider_;
   bool content_is_suitable_for_gpu_rasterization_;
   bool has_gpu_rasterization_trigger_;
   bool use_gpu_rasterization_;
   bool use_msaa_;
   GpuRasterizationStatus gpu_rasterization_status_;
   bool tree_resources_for_gpu_rasterization_dirty_;
   scoped_ptr<TileTaskWorkerPool> tile_task_worker_pool_;
   scoped_ptr<ResourcePool> resource_pool_;
-  scoped_ptr<ResourcePool> staging_resource_pool_;
   scoped_ptr<Renderer> renderer_;
 
   GlobalStateThatImpactsTilePriority global_tile_state_;
 
   // Tree currently being drawn.
   scoped_ptr<LayerTreeImpl> active_tree_;
 
   // In impl-side painting mode, tree with possibly incomplete rasterized
   // content. May be promoted to active by ActivatePendingTree().
   scoped_ptr<LayerTreeImpl> pending_tree_;
@@ skipping 98 matching lines @@
   scoped_ptr<FrameTimingTracker> frame_timing_tracker_;
 
   scoped_ptr<Viewport> viewport_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_HOST_IMPL_H_