Update from chromium https://crrev.com/304586

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 "cc/base/region.h"
 #include "cc/base/scoped_ptr_vector.h"
 #include "cc/resources/picture_layer_tiling.h"
@@ skipping 16 matching lines @@
     LOW_RES,
     LOWER_THAN_LOW_RES
   };
   struct TilingRange {
     TilingRange(size_t start, size_t end) : start(start), end(end) {}
 
     size_t start;
     size_t end;
   };
 
-  explicit PictureLayerTilingSet(PictureLayerTilingClient* client);
+  static scoped_ptr<PictureLayerTilingSet> Create(
+      PictureLayerTilingClient* client);
+
   ~PictureLayerTilingSet();
 
   void SetClient(PictureLayerTilingClient* client);
   const PictureLayerTilingClient* client() const { return client_; }
 
   void RemoveTilesInRegion(const Region& region);
 
   // Make this set of tilings match the same set of content scales from |other|.
   // Delete any tilings that don't meet |minimum_contents_scale|.  Recreate
   // any tiles that intersect |layer_invalidation|.  Update the size of all
   // tilings to |new_layer_bounds|.
   // Returns true if we had at least one high res tiling synced.
   bool SyncTilings(const PictureLayerTilingSet& other,
                    const gfx::Size& new_layer_bounds,
                    const Region& layer_invalidation,
-                   float minimum_contents_scale);
+                   float minimum_contents_scale,
+                   RasterSource* raster_source);
 
   PictureLayerTiling* AddTiling(float contents_scale,
                                 const gfx::Size& layer_bounds);
   size_t num_tilings() const { return tilings_.size(); }
   int NumHighResTilings() const;
   PictureLayerTiling* tiling_at(size_t idx) { return tilings_[idx]; }
   const PictureLayerTiling* tiling_at(size_t idx) const {
     return tilings_[idx];
   }
 
   PictureLayerTiling* TilingAtScale(float scale) const;
 
   // Remove all tilings.
   void RemoveAllTilings();
 
   // Remove one tiling.
   void Remove(PictureLayerTiling* tiling);
 
   // Remove all tiles; keep all tilings.
   void RemoveAllTiles();
 
+  // Update the rects and priorities for tiles based on the given information.
+  bool UpdateTilePriorities(const gfx::Rect& required_rect_in_layer_space,
+                            float ideal_contents_scale,
+                            double current_frame_time_in_seconds,
+                            const Occlusion& occlusion_in_layer_space,
+                            bool can_require_tiles_for_activation);
+
   // For a given rect, iterates through tiles that can fill it.  If no
   // set of tiles with resources can fill the rect, then it will iterate
   // through null tiles with valid geometry_rect() until the rect is full.
   // If all tiles have resources, the union of all geometry_rects will
   // exactly fill rect with no overlap.
   class CC_EXPORT CoverageIterator {
    public:
     CoverageIterator(const PictureLayerTilingSet* set,
       float contents_scale,
       const gfx::Rect& content_rect,
@@ skipping 31 matching lines @@
     Region missing_region_;
     Region::Iterator region_iter_;
   };
 
   void AsValueInto(base::debug::TracedValue* array) const;
   size_t GPUMemoryUsageInBytes() const;
 
   TilingRange GetTilingRange(TilingRangeType type) const;
 
  private:
+  explicit PictureLayerTilingSet(PictureLayerTilingClient* client);
+
   PictureLayerTilingClient* client_;
   ScopedPtrVector<PictureLayerTiling> tilings_;
 
   friend class Iterator;
   DISALLOW_COPY_AND_ASSIGN(PictureLayerTilingSet);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_PICTURE_LAYER_TILING_SET_H_