added gpu_benchmarking_extension boilerplate and hooked it up to a new switch.

content/public/common/content_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.
 
 // Defines all the "content" command-line switches.
 
 #ifndef CONTENT_PUBLIC_COMMON_CONTENT_SWITCHES_H_
 #define CONTENT_PUBLIC_COMMON_CONTENT_SWITCHES_H_
 #pragma once
 
@@ skipping 77 matching lines @@
 CONTENT_EXPORT extern const char kEnableCompositingForFixedPosition[];
 extern const char kEnableCssRegions[];
 extern const char kEnableCssShaders[];
 CONTENT_EXPORT extern const char kEnableDeviceMotion[];
 extern const char kEnableEncryptedMedia[];
 extern const char kEnableFastback[];
 CONTENT_EXPORT extern const char kEnableFixedLayout[];
 CONTENT_EXPORT extern const char kDisableFullScreen[];
 extern const char kEnablePointerLock[];
 extern const char kEnableGamepad[];
+extern const char kEnableGpuBenchmarking[];
 CONTENT_EXPORT extern const char kEnableLogging[];
 extern const char kEnableMediaSource[];
 extern const char kEnablePeerConnection[];
 extern const char kEnableMonitorProfile[];
 extern const char kEnableOriginBoundCerts[];
 extern const char kEnablePartialSwap[];
 extern const char kEnablePinch[];
 extern const char kEnablePreparsedJsCaching[];
 CONTENT_EXPORT extern const char kEnablePrivilegedWebGLExtensions[];
 extern const char kEnablePruneGpuCommandBuffers[];
@@ skipping 103 matching lines @@
 
 #if defined(USE_AURA)
 CONTENT_EXPORT extern const char kFlingTapSuppressMaxDown[];
 CONTENT_EXPORT extern const char kFlingTapSuppressMaxGap[];
 CONTENT_EXPORT extern const char kTestCompositor[];
 #endif
 
 }  // namespace switches
 
 #endif  // CONTENT_PUBLIC_COMMON_CONTENT_SWITCHES_H_