cc: Make tiling interest rect calc based on viewport.

cc/resources/picture_layer_tiling_set.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_PICTURE_LAYER_TILING_SET_H_
 #define CC_RESOURCES_PICTURE_LAYER_TILING_SET_H_
 
 #include <set>
 #include <vector>
 
@@ skipping 22 matching lines @@
   struct TilingRange {
     TilingRange(int start, int end) : start(start), end(end) {}
 
     int start;
     int end;
   };
 
   static scoped_ptr<PictureLayerTilingSet> Create(
       WhichTree tree,
       PictureLayerTilingClient* client,
-      size_t max_tiles_for_interest_area,
+      float tiling_interest_area_viewport_multiplier,
       float skewport_target_time_in_seconds,
       int skewport_extrapolation_limit_in_content);
 
   ~PictureLayerTilingSet();
 
   const PictureLayerTilingClient* client() const { return client_; }
 
   void CleanUpTilings(float min_acceptable_high_res_scale,
                       float max_acceptable_high_res_scale,
                       const std::vector<PictureLayerTiling*>& needed_tilings,
@@ skipping 115 matching lines @@
 
   void AsValueInto(base::trace_event::TracedValue* array) const;
   size_t GPUMemoryUsageInBytes() const;
 
   TilingRange GetTilingRange(TilingRangeType type) const;
 
  private:
   explicit PictureLayerTilingSet(
       WhichTree tree,
       PictureLayerTilingClient* client,
-      size_t max_tiles_for_interest_area,
+      float tiling_interest_area_viewport_multiplier,
       float skewport_target_time_in_seconds,
       int skewport_extrapolation_limit_in_content_pixels);
 
   void CopyTilingsAndPropertiesFromPendingTwin(
       const PictureLayerTilingSet* pending_twin_set,
       const scoped_refptr<RasterSource>& raster_source,
       const Region& layer_invalidation);
 
   // Remove one tiling.
   void Remove(PictureLayerTiling* tiling);
   void VerifyTilings(const PictureLayerTilingSet* pending_twin_set) const;
 
   ScopedPtrVector<PictureLayerTiling> tilings_;
 
-  const size_t max_tiles_for_interest_area_;
+  const float tiling_interest_area_viewport_multiplier_;
   const float skewport_target_time_in_seconds_;
   const int skewport_extrapolation_limit_in_content_pixels_;
   WhichTree tree_;
   PictureLayerTilingClient* client_;
 
   friend class Iterator;
   DISALLOW_COPY_AND_ASSIGN(PictureLayerTilingSet);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_PICTURE_LAYER_TILING_SET_H_