Add latency measurement system

cc/output_surface.h

 // Copyright 2012 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_OUTPUT_SURFACE_H_
 #define CC_OUTPUT_SURFACE_H_
 
 #define USE_CC_OUTPUT_SURFACE // TODO(danakj): Remove this.
 
 #include "cc/cc_export.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebCompositorOutputSurface.h"
 
 namespace WebKit {
 class WebGraphicsContext3D;
 }
 
 namespace cc {
 
 class CompositorFrame;
 class OutputSurfaceClient;
 class SoftwareOutputDevice;
+struct LatencyInfo;
 
 // Represents the output surface for a compositor. The compositor owns
 // and manages its destruction. Its lifetime is:
 //   1. Created on the main thread by the LayerTreeHost through its client.
 //   2. Passed to the compositor thread and bound to a client via BindToClient.
 //      From here on, it will only be used on the compositor thread.
 //   3. If the 3D context is lost, then the compositor will delete the output
 //      surface (on the compositor thread) and go back to step 1.
 class CC_EXPORT OutputSurface : public WebKit::WebCompositorOutputSurface {
  public:
@@ skipping 17 matching lines @@
   // Obtain the 3d context or the software device associated with this output
   // surface. Either of these may return a null pointer, but not both.
   // In the event of a lost context, the entire output surface should be
   // recreated.
   virtual WebKit::WebGraphicsContext3D* Context3D() const = 0;
   virtual SoftwareOutputDevice* SoftwareDevice() const = 0;
 
   // Sends frame data to the parent compositor. This should only be called when
   // capabilities().has_parent_compositor.
   virtual void SendFrameToParentCompositor(const CompositorFrame&) {}
+
+  virtual void SetLatencyInfo(const LatencyInfo&) {}
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_SURFACE_H_