cc: Low quality support for low res tiles

cc/resources/tile.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_TILE_H_
 #define CC_RESOURCES_TILE_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
@@ skipping 17 matching lines @@
        gfx::Rect content_rect,
        gfx::Rect opaque_rect,
        float contents_scale,
        int layer_id,
        int source_frame_number);
 
   PicturePileImpl* picture_pile() {
     return picture_pile_.get();
   }
 
+  const PicturePileImpl* picture_pile() const {
+    return picture_pile_.get();
+  }
+
   const TilePriority& priority(WhichTree tree) const {
     return priority_[tree];
   }
 
   TilePriority combined_priority() const {
     return TilePriority(priority_[ACTIVE_TREE],
                         priority_[PENDING_TREE]);
   }
 
   void SetPriority(WhichTree tree, const TilePriority& priority) {
@@ skipping 29 matching lines @@
 
   int source_frame_number() const { return source_frame_number_; }
 
   void set_picture_pile(scoped_refptr<PicturePileImpl> pile) {
     DCHECK(pile->CanRaster(contents_scale_, content_rect_));
     picture_pile_ = pile;
   }
 
   // For test only methods.
   bool HasRasterTaskForTesting() const {
-    return !managed_state().raster_task.is_null();
+    return !managed_state().pending_tile_versions.empty();
   }
   void ResetRasterTaskForTesting() {
-    managed_state().raster_task.Reset();
+    managed_state().pending_tile_versions.clear();
   }
 
  private:
   // Methods called by by tile manager.
   friend class TileManager;
   friend class BinComparator;
   ManagedTileState& managed_state() { return managed_state_; }
   const ManagedTileState& managed_state() const { return managed_state_; }
 
   inline size_t bytes_consumed_if_allocated() const {
@@ skipping 16 matching lines @@
   ManagedTileState managed_state_;
   int layer_id_;
   int source_frame_number_;
 
   DISALLOW_COPY_AND_ASSIGN(Tile);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_TILE_H_