Route D3D VSync signal to Compositor

ui/gl/gl_switches.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_GL_GL_SWITCHES_H_
 #define UI_GL_GL_SWITCHES_H_
 
 // Defines all the command-line switches used by ui/gl.
 
+#include "base/feature_list.h"
 #include "ui/gl/gl_export.h"
 
 namespace gl {
 
 // The GL implementation names that can be passed to --use-gl.
 GL_EXPORT extern const char kGLImplementationDesktopName[];
 GL_EXPORT extern const char kGLImplementationOSMesaName[];
 GL_EXPORT extern const char kGLImplementationAppleName[];
 GL_EXPORT extern const char kGLImplementationEGLName[];
 GL_EXPORT extern const char kGLImplementationANGLEName[];
@@ skipping 37 matching lines @@
 
 // These flags are used by the test harness code, not passed in by users.
 GL_EXPORT extern const char kDisableGLDrawingForTests[];
 GL_EXPORT extern const char kOverrideUseSoftwareGLForTests[];
 
 GL_EXPORT extern const char* kGLSwitchesCopiedFromGpuProcessHost[];
 GL_EXPORT extern const int kGLSwitchesCopiedFromGpuProcessHostNumSwitches;
 
 }  // namespace switches
 
+namespace features {
+
+#if defined(OS_WIN)
+GL_EXPORT extern const base::Feature kD3DVsync;
+#endif  // defined(OS_WIN)
+
+}  // namespace features
+
 #endif  // UI_GL_GL_SWITCHES_H_