Track the cost of impl-side painting.

cc/tile_manager.h

Index: cc/tile_manager.h
===================================================================
--- cc/tile_manager.h	(revision 170195)
+++ cc/tile_manager.h	(working copy)
@@ -20,6 +20,7 @@
 
 class Tile;
 class TileVersion;
+class RenderingStats;
 class ResourceProvider;
 
 class CC_EXPORT TileManagerClient {
@@ -74,6 +75,8 @@
 
   void ManageTiles();
 
+  void renderingStats(RenderingStats* stats);
+
  protected:
   // Methods called by Tile
   friend class Tile;
@@ -90,7 +93,8 @@
   void OnRasterTaskCompleted(
       scoped_refptr<Tile>,
       ResourceProvider::ResourceId,
-      scoped_refptr<PicturePileImpl>);
+      scoped_refptr<PicturePileImpl>,
+      RenderingStats*);
   void DidFinishTileInitialization(Tile*, ResourceProvider::ResourceId);
 
   TileManagerClient* client_;
@@ -104,6 +108,8 @@
   typedef std::vector<Tile*> TileVector;
   TileVector tiles_;
   TileVector tiles_that_need_to_be_rasterized_;
+
+  RenderingStats rendering_stats_;
 };
 
 }  // namespace cc