cc: Compute the inflated rect to cover a fixed number of tiles.

cc/picture_layer_tiling.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_PICTURE_LAYER_TILING_H_
 #define CC_PICTURE_LAYER_TILING_H_
 
 #include "base/basictypes.h"
 #include "base/hash_tables.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 53 matching lines @@
       all_tiles.push_back(it->second);
     return all_tiles;
   }
 
   enum LayerDeviceAlignment {
     LayerDeviceAlignmentUnknown,
     LayerAlignedToDevice,
     LayerNotAlignedToDevice,
   };
 
+  static gfx::Rect ExpandRectEquallyToAreaBoundedBy(
+      gfx::Rect starting_rect,
+      int64 target_area,
+      gfx::Rect bounding_rect);
+
   // Iterate over all tiles to fill content_rect.  Even if tiles are invalid
   // (i.e. no valid resource) this tiling should still iterate over them.
   // The union of all geometry_rect calls for each element iterated over should
   // exactly equal content_rect and no two geometry_rects should intersect.
   class CC_EXPORT Iterator {
    public:
     Iterator();
     Iterator(const PictureLayerTiling* tiling,
         float dest_scale,
         gfx::Rect rect,
@@ skipping 81 matching lines @@
   TileResolution resolution_;
   int last_source_frame_number_;
   double last_impl_frame_time_;
 
   friend class Iterator;
 };
 
 }  // namespace cc
 
 #endif  // CC_PICTURE_LAYER_TILING_H_