Cluster invalidation rectangles into coherent regions to lessen SkPicture re-recording

cc/resources/picture_pile_base.h

 // Copyright 2013 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_PICTURE_PILE_BASE_H_
 #define CC_RESOURCES_PICTURE_PILE_BASE_H_
 
 #include <list>
 #include <utility>
 
@@ skipping 52 matching lines @@
   typedef std::pair<int, int> PictureMapKey;
   typedef base::hash_map<PictureMapKey, PictureInfo> PictureMap;
 
   virtual ~PicturePileBase();
 
   int num_raster_threads() { return num_raster_threads_; }
   int buffer_pixels() const { return tiling_.border_texels(); }
   void Clear();
 
   gfx::Rect PaddedRect(const PictureMapKey& key);
+  gfx::Rect PadRect(gfx::Rect rect);
 
   // A picture pile is a tiled set of pictures. The picture map is a map of tile
   // indices to picture infos.
   PictureMap picture_map_;
   TilingData tiling_;
   Region recorded_region_;
   float min_contents_scale_;
   SkTileGridPicture::TileGridInfo tile_grid_info_;
   SkColor background_color_;
   int slow_down_raster_scale_factor_for_debug_;
   bool contents_opaque_;
   bool show_debug_picture_borders_;
   bool clear_canvas_with_debug_color_;
   int num_raster_threads_;
 
  private:
   void SetBufferPixels(int buffer_pixels);
 
   friend class base::RefCounted<PicturePileBase>;
   DISALLOW_COPY_AND_ASSIGN(PicturePileBase);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_PICTURE_PILE_BASE_H_