cc:: Add RenderingStatsInstrumentation to manage collection of RenderingStats

cc/raster_worker_pool.cc

Index: cc/raster_worker_pool.cc
diff --git a/cc/raster_worker_pool.cc b/cc/raster_worker_pool.cc
index 25ee33b1c9e17951c2afd36d993596b2d67d023e..fc382e53f14c9859f33d5a58acb30c6a3b034a08 100644
--- a/cc/raster_worker_pool.cc
+++ b/cc/raster_worker_pool.cc
@@ -25,14 +25,12 @@ class RasterWorkerPoolTaskImpl : public internal::WorkerPoolTask {
 
   virtual bool IsCheap() OVERRIDE { return is_cheap_; }
 
-  virtual void Run(RenderingStats* rendering_stats) OVERRIDE {
-    task_.Run(picture_pile_.get(), rendering_stats);
+  virtual void Run() OVERRIDE {
+    task_.Run(picture_pile_.get());
   }
 
-  virtual void RunOnThread(
-      RenderingStats* rendering_stats, unsigned thread_index) OVERRIDE {
-    task_.Run(picture_pile_->GetCloneForDrawingOnThread(thread_index),
-              rendering_stats);
+  virtual void RunOnThread(unsigned thread_index) OVERRIDE {
+    task_.Run(picture_pile_->GetCloneForDrawingOnThread(thread_index));
   }
 
  private: