[Do not submit] D3DKMTWaitForVerticalBlankEvent VSync prototype

content/browser/compositor/browser_compositor_output_surface.h

Index: content/browser/compositor/browser_compositor_output_surface.h
diff --git a/content/browser/compositor/browser_compositor_output_surface.h b/content/browser/compositor/browser_compositor_output_surface.h
index 8c8f56cac0d11ffea21a8139a87c82c69e2c536f..f1790f1d5705d8b8c808d86b721cdc7c55d591d5 100644
--- a/content/browser/compositor/browser_compositor_output_surface.h
+++ b/content/browser/compositor/browser_compositor_output_surface.h
@@ -25,6 +25,7 @@ enum class SwapResult;
 
 namespace content {
 class ReflectorImpl;
+class GpuVSyncControl;
 
 class CONTENT_EXPORT BrowserCompositorOutputSurface
     : public cc::OutputSurface {
@@ -44,6 +45,9 @@ class CONTENT_EXPORT BrowserCompositorOutputSurface
   // Called when |reflector_| was updated.
   virtual void OnReflectorChanged();
 
+  // Called to determine if this type of OutputSurface provides GPU VSync.
+  virtual GpuVSyncControl* GetVSyncControl();
+
 #if defined(OS_MACOSX)
   virtual void SetSurfaceSuspendedForRecycle(bool suspended) = 0;
 #endif