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_numerator,
+                                                uint32 *interval_denominator) {
+  lock_.AssertAcquired();
+
+  DWM_TIMING_INFO timingInfo;

[apatrick_chromium, 2012/07/30 19:43:31]

timing_info

+  timingInfo.cbSize = sizeof(timingInfo);
+  HRESULT gctiResult = DwmGetCompositionTimingInfo(window_, &timingInfo);

[apatrick_chromium, 2012/07/30 19:43:31]

I'd just call this result. otherwise gcti_result.

[brianderson, 2012/07/30 20:16:39]

Artifact of previous code that had multiple result types.  Fixed.

+  if (gctiResult != S_OK)
+    return;
+
+  *timebase = base::TimeTicks::FromQPCValue(
+      static_cast<LONGLONG>(timingInfo.qpcVBlank));
+  // Swap the numerator/denominator to convert frequency to period.
+  *interval_numerator = timingInfo.rateRefresh.uiDenominator;
+  *interval_denominator = timingInfo.rateRefresh.uiNumerator;
+}
+
 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();
 }