Disable accelerated 2d canvas and put it back as an option in about:flags.

content/public/common/content_switches.cc

 // Copyright (c) 2011 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/public/common/content_switches.h"
 
 namespace switches {
 
 // By default, file:// URIs cannot read other file:// URIs. This is an
 // override for developers who need the old behavior for testing.
@@ skipping 21 matching lines @@
 // Run Chrome in Chrome Frame mode. This means that Chrome expects to be run
 // as a dependent process of the Chrome Frame plugin.
 const char kChromeFrame[]                   = "chrome-frame";
 
 // Disables client-visible 3D APIs, in particular WebGL and Pepper 3D.
 // This is controlled by policy and is kept separate from the other
 // enable/disable switches to avoid accidentally regressing the policy
 // support for controlling access to these APIs.
 const char kDisable3DAPIs[]                 = "disable-3d-apis";
 
-// Disable gpu-accelerated 2d canvas.
-const char kDisableAccelerated2dCanvas[]    = "disable-accelerated-2d-canvas";
-
 // Disables accelerated compositing.
 const char kDisableAcceleratedCompositing[] = "disable-accelerated-compositing";
 
 // Disables the hardware acceleration of 3D CSS and animation.
 const char kDisableAcceleratedLayers[]      = "disable-accelerated-layers";
 
 // Disables the hardware acceleration of plugins.
 const char kDisableAcceleratedPlugins[]     = "disable-accelerated-plugins";
 
 // Disables GPU accelerated video display.
@@ skipping 439 matching lines @@
 // instead of NSS for SSL.
 const char kUseSystemSSL[]                  = "use-system-ssl";
 #endif
 
 #if !defined(OFFICIAL_BUILD)
 // Causes the renderer process to throw an assertion on launch.
 const char kRendererCheckFalseTest[]        = "renderer-check-false-test";
 #endif
 
 }  // namespace switches