cc: Reduce time spent in AssignGpuMemoryToTiles().

cc/tile_manager.h

Index: cc/tile_manager.h
diff --git a/cc/tile_manager.h b/cc/tile_manager.h
index d80e2f1a0b1860441c47e99a947c139821a788a8..d0089a70741de247f97549f1e6959902206e37dd 100644
--- a/cc/tile_manager.h
+++ b/cc/tile_manager.h
@@ -101,6 +101,7 @@ class CC_EXPORT TileManager {
       scoped_refptr<Tile>,
       scoped_ptr<ResourcePool::Resource>,
       scoped_refptr<PicturePileImpl>,
+      int manage_tiles_call_count_when_dispatched,
       RenderingStats*);
   void DidFinishTileInitialization(Tile*);
   void DispatchImageDecodingTasksForTile(Tile*);
@@ -112,6 +113,7 @@ class CC_EXPORT TileManager {
   TileManagerClient* client_;
   scoped_ptr<ResourcePool> resource_pool_;
   bool manage_tiles_pending_;
+  int manage_tiles_call_count_;
   bool check_for_completed_set_pixels_pending_;
 
   GlobalStateThatImpactsTilePriority global_state_;