cc: Don't swap PictureLayerTilingSet on activate.

cc/resources/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_RESOURCES_PICTURE_LAYER_TILING_H_
 #define CC_RESOURCES_PICTURE_LAYER_TILING_H_
 
 #include <set>
 #include <utility>
 #include <vector>
@@ skipping 103 matching lines @@
     Phase phase_;
 
     Tile* current_tile_;
     TilingData::Iterator visible_iterator_;
     TilingData::SpiralDifferenceIterator spiral_iterator_;
   };
 
   ~PictureLayerTiling();
 
   // Create a tiling with no tiles.  CreateTiles must be called to add some.
+  // TODO(danakj): Pass the raster_source here instead of the size, store the
+  // raster source instead of layer bounds?
   static scoped_ptr<PictureLayerTiling> Create(
       float contents_scale,
       const gfx::Size& layer_bounds,
       PictureLayerTilingClient* client);
   gfx::Size layer_bounds() const { return layer_bounds_; }
   void UpdateTilesToCurrentRasterSource(RasterSource* raster_source,
                                         const Region& layer_invalidation,
-                                        const gfx::Size& new_layer_bounds);
+                                        const gfx::Size& layer_bounds);
   void CreateMissingTilesInLiveTilesRect();
-  void RemoveTilesInRegion(const Region& layer_region);
 
-  void SetClient(PictureLayerTilingClient* client);
+  void CloneTilesAndPropertiesFrom(const PictureLayerTiling& other);
+
   void set_resolution(TileResolution resolution) { resolution_ = resolution; }
   TileResolution resolution() const { return resolution_; }
   void set_can_require_tiles_for_activation(bool can_require_tiles) {
     can_require_tiles_for_activation_ = can_require_tiles;
   }
 
   gfx::Size tiling_size() const { return tiling_data_.tiling_size(); }
   gfx::Rect live_tiles_rect() const { return live_tiles_rect_; }
   gfx::Size tile_size() const { return tiling_data_.max_texture_size(); }
   float contents_scale() const { return contents_scale_; }
@@ skipping 159 matching lines @@
 
   void UpdateEvictionCacheIfNeeded(TreePriority tree_priority);
   const std::vector<Tile*>* GetEvictionTiles(TreePriority tree_priority,
                                              EvictionCategory category);
 
   void Invalidate(const Region& layer_region);
 
   void DoInvalidate(const Region& layer_region,
                     bool recreate_invalidated_tiles);
 
+  // Save the required data for computing tile priorities later.
+  void UpdateTilePriorityRects(float content_to_screen_scale_,
+                               const gfx::Rect& visible_rect_in_content_space,
+                               const gfx::Rect& skewport,
+                               const gfx::Rect& soon_border_rect,
+                               const gfx::Rect& eventually_rect,
+                               const Occlusion& occlusion_in_layer_space);
+
   void UpdateTileAndTwinPriority(Tile* tile) const;
   void UpdateTilePriority(Tile* tile) const;
 
   // Given properties.
   float contents_scale_;
   gfx::Size layer_bounds_;
   TileResolution resolution_;
   PictureLayerTilingClient* client_;
 
   // Internal data.
   TilingData tiling_data_;
   TileMap tiles_;  // It is not legal to have a NULL tile in the tiles_ map.
   gfx::Rect live_tiles_rect_;
 
   // State saved for computing velocities based upon finite differences.
   double last_impl_frame_time_in_seconds_;
   gfx::Rect last_viewport_in_layer_space_;
   gfx::Rect last_visible_rect_in_content_space_;
-  float content_to_screen_scale_;
 
   bool can_require_tiles_for_activation_;
 
-  // Iteration rects in content space
+  // Iteration rects in content space.
   gfx::Rect current_visible_rect_;
   gfx::Rect current_skewport_rect_;
   gfx::Rect current_soon_border_rect_;
   gfx::Rect current_eventually_rect_;
+  // Other properties used for tile iteration and prioritization.
+  float current_content_to_screen_scale_;
+  Occlusion current_occlusion_in_layer_space_;
 
   bool has_visible_rect_tiles_;
   bool has_skewport_rect_tiles_;
   bool has_soon_border_rect_tiles_;
   bool has_eventually_rect_tiles_;
 
-  Occlusion current_occlusion_in_layer_space_;
-
   // TODO(reveman): Remove this in favour of an array of eviction_tiles_ when we
   // change all enums to have a consistent way of getting the count/last
   // element.
   std::vector<Tile*> eviction_tiles_now_;
   std::vector<Tile*> eviction_tiles_now_and_required_for_activation_;
   std::vector<Tile*> eviction_tiles_soon_;
   std::vector<Tile*> eviction_tiles_soon_and_required_for_activation_;
   std::vector<Tile*> eviction_tiles_eventually_;
   std::vector<Tile*> eviction_tiles_eventually_and_required_for_activation_;
 
   bool eviction_tiles_cache_valid_;
   TreePriority eviction_cache_tree_priority_;
 
  private:
   DISALLOW_ASSIGN(PictureLayerTiling);
 
   RectExpansionCache expansion_cache_;
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_PICTURE_LAYER_TILING_H_