cc: Declare high res tilings to not have low res content.

cc/tiles/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_TILES_PICTURE_LAYER_TILING_H_
 #define CC_TILES_PICTURE_LAYER_TILING_H_
 
 #include <map>
 #include <utility>
 #include <vector>
@@ skipping 95 matching lines @@
   void Invalidate(const Region& layer_invalidation);
   void CreateMissingTilesInLiveTilesRect();
   void TakeTilesAndPropertiesFrom(PictureLayerTiling* pending_twin,
                                   const Region& layer_invalidation);
 
   bool IsTileRequiredForActivation(const Tile* tile) const;
   bool IsTileRequiredForDraw(const Tile* tile) const;
 
   void set_resolution(TileResolution resolution) {
     resolution_ = resolution;
-    was_ever_low_resolution_ |= resolution == LOW_RESOLUTION;
+    may_contain_low_resolution_tiles_ |= resolution == LOW_RESOLUTION;
   }
   TileResolution resolution() const { return resolution_; }
-  bool was_ever_low_resolution() const { return was_ever_low_resolution_; }
+  bool may_contain_low_resolution_tiles() const {
+    return may_contain_low_resolution_tiles_;
+  }
+  void reset_may_contain_low_resolution_tiles() {
+    may_contain_low_resolution_tiles_ = false;
+  }
   void set_can_require_tiles_for_activation(bool can_require_tiles) {
     can_require_tiles_for_activation_ = can_require_tiles;
   }
 
   RasterSource* raster_source() const { return raster_source_.get(); }
   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_; }
   const TilingData* tiling_data() const { return &tiling_data_; }
@@ skipping 236 matching lines @@
   const size_t tiling_interest_area_padding_;
   const float skewport_target_time_in_seconds_;
   const int skewport_extrapolation_limit_in_content_pixels_;
 
   // Given properties.
   const float contents_scale_;
   PictureLayerTilingClient* const client_;
   const WhichTree tree_;
   scoped_refptr<RasterSource> raster_source_;
   TileResolution resolution_;
-  bool was_ever_low_resolution_;
+  bool may_contain_low_resolution_tiles_;
 
   // 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_;
 
   gfx::Rect last_viewport_in_layer_space_;
   // State saved for computing velocities based upon finite differences.
   FrameVisibleRect visible_rect_history_[2];
 
@@ skipping 14 matching lines @@
   bool has_eventually_rect_tiles_;
   bool all_tiles_done_;
 
  private:
   DISALLOW_ASSIGN(PictureLayerTiling);
 };
 
 }  // namespace cc
 
 #endif  // CC_TILES_PICTURE_LAYER_TILING_H_