cc: GPU rasterize tiles synchronously in PrepareToDraw.

cc/resources/tile.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_RESOURCES_TILE_H_
 #define CC_RESOURCES_TILE_H_
 
 #include "base/memory/ref_counted.h"
 #include "cc/base/ref_counted_managed.h"
 #include "cc/resources/managed_tile_state.h"
@@ skipping 125 matching lines @@
 
   void set_tiling_index(int i, int j) {
     tiling_i_index_ = i;
     tiling_j_index_ = j;
   }
   int tiling_i_index() const { return tiling_i_index_; }
   int tiling_j_index() const { return tiling_j_index_; }
 
  private:
   friend class TileManager;
+  friend class GpuRasterizer;
+  friend class SoftwareRasterizer;
   friend class PrioritizedTileSet;
   friend class FakeTileManager;
   friend class BinComparator;
   friend class FakePictureLayerImpl;
 
   // Methods called by by tile manager.
   Tile(TileManager* tile_manager,
        RasterSource* raster_source,
        const gfx::Size& tile_size,
        const gfx::Rect& content_rect,
@@ skipping 28 matching lines @@
 
   Id id_;
   static Id s_next_id_;
 
   DISALLOW_COPY_AND_ASSIGN(Tile);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_TILE_H_