Add a user pref in Settings to disable all GPU features.

chrome/browser/browser_process_impl.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.
 
 // When each service is created, we set a flag indicating this. At this point,
 // the service initialization could fail or succeed. This allows us to remember
 // if we tried to create a service, and not try creating it over and over if
 // the creation failed.
 
 #ifndef CHROME_BROWSER_BROWSER_PROCESS_IMPL_H_
@@ skipping 74 matching lines @@
   virtual extensions::EventRouterForwarder*
         extension_event_router_forwarder() OVERRIDE;
   virtual NotificationUIManager* notification_ui_manager() OVERRIDE;
 #if defined(ENABLE_MESSAGE_CENTER)
   virtual message_center::MessageCenter* message_center() OVERRIDE;
 #endif
   virtual policy::BrowserPolicyConnector* browser_policy_connector() OVERRIDE;
   virtual policy::PolicyService* policy_service() OVERRIDE;
   virtual IconManager* icon_manager() OVERRIDE;
   virtual GLStringManager* gl_string_manager() OVERRIDE;
+  virtual GpuModeManager* gpu_mode_manager() OVERRIDE;
   virtual RenderWidgetSnapshotTaker* GetRenderWidgetSnapshotTaker() OVERRIDE;
   virtual AutomationProviderList* GetAutomationProviderList() OVERRIDE;
   virtual void CreateDevToolsHttpProtocolHandler(
       Profile* profile,
       chrome::HostDesktopType host_desktop_type,
       const std::string& ip,
       int port,
       const std::string& frontend_url) OVERRIDE;
   virtual unsigned int AddRefModule() OVERRIDE;
   virtual unsigned int ReleaseModule() OVERRIDE;
@@ skipping 77 matching lines @@
   scoped_ptr<ProfileManager> profile_manager_;
 
   bool created_local_state_;
   scoped_ptr<PrefService> local_state_;
 
   bool created_icon_manager_;
   scoped_ptr<IconManager> icon_manager_;
 
   scoped_ptr<GLStringManager> gl_string_manager_;
 
+  scoped_ptr<GpuModeManager> gpu_mode_manager_;
+
   scoped_refptr<extensions::EventRouterForwarder>
       extension_event_router_forwarder_;
 
 #if !defined(OS_ANDROID)
   scoped_ptr<RemoteDebuggingServer> remote_debugging_server_;
 
   // Bookmark prompt controller displays the prompt for frequently visited URL.
   scoped_ptr<BookmarkPromptController> bookmark_prompt_controller_;
 #endif
 
@@ skipping 95 matching lines @@
 #endif
 
   // TODO(eroman): Remove this when done debugging 113031. This tracks
   // the callstack which released the final module reference count.
   base::debug::StackTrace release_last_reference_callstack_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserProcessImpl);
 };
 
 #endif  // CHROME_BROWSER_BROWSER_PROCESS_IMPL_H_