NOT READY FOR REVIEW - switch to a subscriber model for rendering stats

cc/single_thread_proxy.h

Index: cc/single_thread_proxy.h
diff --git a/cc/single_thread_proxy.h b/cc/single_thread_proxy.h
index 93f8c09a6a3bc927c71cbe1c9a6532f96695d487..48120249c1652ecdb56f2ad11392d0b5f5c2aa44 100644
--- a/cc/single_thread_proxy.h
+++ b/cc/single_thread_proxy.h
@@ -15,6 +15,7 @@
 namespace cc {
 
 class LayerTreeHost;
+class RenderingStatsSubscriber;
 
 class SingleThreadProxy : public Proxy, LayerTreeHostImplClient {
 public:
@@ -32,6 +33,8 @@ public:
     virtual bool initializeRenderer() OVERRIDE;
     virtual bool recreateContext() OVERRIDE;
     virtual void renderingStats(RenderingStats*) OVERRIDE;
+    virtual void startRecordingRenderingStats() OVERRIDE;
+    virtual void stopRecordingRenderingStats(RenderingStats*) OVERRIDE;
     virtual const RendererCapabilities& rendererCapabilities() const OVERRIDE;
     virtual void loseContext() OVERRIDE;
     virtual void setNeedsAnimate() OVERRIDE;
@@ -85,6 +88,7 @@ private:
 
     base::TimeDelta m_totalCommitTime;
     size_t m_totalCommitCount;
+    scoped_ptr<RenderingStatsSubscriber> m_renderingStatsSubscriber;
 };
 
 // For use in the single-threaded case. In debug builds, it pretends that the