cc:: Add RenderingStatsInstrumentation to manage collection of RenderingStats

cc/raster_worker_pool.h

Index: cc/raster_worker_pool.h
diff --git a/cc/raster_worker_pool.h b/cc/raster_worker_pool.h
index f9fe4cef88cd566407e6540bdff591611c581d4b..9b2d81d305bd0067f39183d77afe84aae6613699 100644
--- a/cc/raster_worker_pool.h
+++ b/cc/raster_worker_pool.h
@@ -15,7 +15,7 @@ class PicturePileImpl;
 // A worker thread pool that runs raster tasks.
 class RasterWorkerPool : public WorkerPool {
  public:
-  typedef base::Callback<void(PicturePileImpl*, RenderingStats*)>
+  typedef base::Callback<void(PicturePileImpl*)>
       RasterCallback;
 
   virtual ~RasterWorkerPool();