Read compositor VSync information from platform, when possible

content/browser/renderer_host/media/desktop_capture_device_aura.cc

 // 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.
 
 #include "content/browser/renderer_host/media/desktop_capture_device_aura.h"
 
 #include "base/logging.h"
 #include "base/timer/timer.h"
 #include "cc/output/copy_output_request.h"
 #include "cc/output/copy_output_result.h"
@@ skipping 95 matching lines @@
   virtual void OnWindowDestroyed(aura::Window* window) OVERRIDE;
 
   // Implements ui::CompositorObserver.
   virtual void OnCompositingDidCommit(ui::Compositor* compositor) OVERRIDE {}
   virtual void OnCompositingStarted(ui::Compositor* compositor,
                                     base::TimeTicks start_time) OVERRIDE {}
   virtual void OnCompositingEnded(ui::Compositor* compositor) OVERRIDE;
   virtual void OnCompositingAborted(ui::Compositor* compositor) OVERRIDE {}
   virtual void OnCompositingLockStateChanged(
       ui::Compositor* compositor) OVERRIDE {}
-  virtual void OnUpdateVSyncParameters(ui::Compositor* compositor,
-                                       base::TimeTicks timebase,
-                                       base::TimeDelta interval) OVERRIDE {}
 
  private:
   // Captures a frame.
   // |dirty| is false for timer polls and true for compositor updates.
   void Capture(bool dirty);
 
   // Update capture size. Must be called on the UI thread.
   void UpdateCaptureSize();
 
   // Response callback for cc::Layer::RequestCopyOfOutput().
@@ skipping 313 matching lines @@
     scoped_ptr<Client> client) {
   DVLOG(1) << "Allocating " << params.requested_format.frame_size.ToString();
   impl_->AllocateAndStart(params, client.Pass());
 }
 
 void DesktopCaptureDeviceAura::StopAndDeAllocate() {
   impl_->StopAndDeAllocate();
 }
 
 }  // namespace content