Use DwmGetCompositionTimingInfo to get vsync info on Windows

ui/surface/accelerated_surface_win.h

 // Copyright (c) 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 UI_SURFACE_ACCELERATED_SURFACE_WIN_H_
 #define UI_SURFACE_ACCELERATED_SURFACE_WIN_H_
 
 #include <d3d9.h>
 
 #include "base/callback_forward.h"
@@ skipping 52 matching lines @@
   // These member functions are called on the PresentThread with which the
   // presenter has affinity.
   void DoPresentAndAcknowledge(
       const gfx::Size& size,
       int64 surface_handle,
       const base::Callback<void(bool)>& completion_task);
   void DoSuspend();
   void DoPresent(HDC dc, bool* presented);
   bool DoRealPresent(HDC dc);
   void DoReleaseSurface();
+  void GetPresentationStats(base::TimeTicks *timebase,

[jbates, 2012/07/28 01:35:30]

comments + n/d abbrev.

+                            uint32 *interval_n,
+                            uint32 *interval_d);
 
   // The thread with which this presenter has affinity.
   PresentThread* const present_thread_;
 
   // The window that is presented to.
   gfx::NativeWindow window_;
 
   // The lock is taken while any thread is calling the object, except those that
   // simply post from the main thread to the present thread via the immutable
   // present_thread_ member.
@@ skipping 45 matching lines @@
 
   // Indicates that the surface has become invisible.
   void WasHidden();
 
  private:
   const scoped_refptr<AcceleratedPresenter> presenter_;
   DISALLOW_COPY_AND_ASSIGN(AcceleratedSurface);
 };
 
 #endif  // UI_SURFACE_ACCELERATED_SURFACE_WIN_H_