Use DwmGetCompositionTimingInfo to get vsync info on Windows

ui/surface/accelerated_surface_win.cc

 // 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.
 
 #include "ui/surface/accelerated_surface_win.h"
 
+#include <dwmapi.h>
 #include <windows.h>
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/file_path.h"
 #include "base/lazy_instance.h"
@@ skipping 809 matching lines @@
 void AcceleratedPresenter::DoSuspend() {
   base::AutoLock locked(lock_);
   swap_chain_ = NULL;
 }
 
 void AcceleratedPresenter::DoReleaseSurface() {
   base::AutoLock locked(lock_);
   source_texture_.Release();
 }
 
+void AcceleratedPresenter::GetPresentationStats(base::TimeTicks *timebase,
+                                                uint32 *interval_n,
+                                                uint32 *interval_d) {
+  lock_.AssertAcquired();
+
+  DWM_TIMING_INFO timingInfo;
+  timingInfo.cbSize = sizeof(timingInfo);
+  HRESULT gctiResult = DwmGetCompositionTimingInfo(window_, &timingInfo);
+  if (gctiResult != S_OK)
+      return;

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

2 space indent

+
+  // TODO: For scheduling purposes we can choose to synchronize to the
+  // vblank or composition time.  If the composition time jitters, it may
+  // be better to rely on the vblank only.  It may be even better to have
+  // animations depend on the vblank, but touch events and rendering to
+  // depend on composition time eventually.
+  *timebase = base::TimeTicks::FromQPCValue(
+                static_cast<LONGLONG>(timingInfo.qpcCompose));
+  *interval_n = timingInfo.rateCompose.uiNumerator;
+  *interval_d = timingInfo.rateCompose.uiDenominator;
+}
+
 AcceleratedSurface::AcceleratedSurface(gfx::NativeWindow window)
     : presenter_(g_accelerated_presenter_map.Pointer()->CreatePresenter(
           window)) {
 }
 
 AcceleratedSurface::~AcceleratedSurface() {
   g_accelerated_presenter_map.Pointer()->RemovePresenter(presenter_);
   presenter_->Invalidate();
 }
 
 bool AcceleratedSurface::Present(HDC dc) {
   return presenter_->Present(dc);
 }
 
 bool AcceleratedSurface::CopyTo(const gfx::Size& size, void* buf) {
   return presenter_->CopyTo(size, buf);
 }
 
 void AcceleratedSurface::Suspend() {
   presenter_->Suspend();
 }
 
 void AcceleratedSurface::WasHidden() {
   presenter_->WasHidden();
 }