cc: Plumbing for impl thread micro benchmarks

cc/debug/micro_benchmark.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_DEBUG_MICRO_BENCHMARK_H_
 #define CC_DEBUG_MICRO_BENCHMARK_H_
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 
 namespace base {
 class Value;
+class MessageLoopProxy;
 }  // namespace base
 
 namespace cc {
 
 class LayerTreeHost;
 class Layer;
 class PictureLayer;
+class MicroBenchmarkImpl;
 class MicroBenchmark {
  public:
   typedef base::Callback<void(scoped_ptr<base::Value>)> DoneCallback;
 
   explicit MicroBenchmark(const DoneCallback& callback);
   virtual ~MicroBenchmark();
 
   bool IsDone() const;
   virtual void DidUpdateLayers(LayerTreeHost* host);
 
   virtual void RunOnLayer(Layer* layer);
   virtual void RunOnLayer(PictureLayer* layer);
 
+  virtual scoped_ptr<MicroBenchmarkImpl> CreateBenchmarkImpl(
+      scoped_refptr<base::MessageLoopProxy> origin_loop);
+
  protected:
   void NotifyDone(scoped_ptr<base::Value> result);
 
  private:
   DoneCallback callback_;
   bool is_done_;
 };
 
 }  // namespace cc
 
 #endif  // CC_DEBUG_MICRO_BENCHMARK_H_