This change adds the apple software renderer as an option on Chrome/Mac. It's enabled by passing...

ui/gfx/gl/gl_implementation_mac.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 "base/base_paths.h"
 #include "base/file_path.h"
 #include "base/logging.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/mac/foundation_util.h"
 #include "base/native_library.h"
 #include "base/path_service.h"
 #include "ui/gfx/gl/gl_bindings.h"
 #include "ui/gfx/gl/gl_implementation.h"
 
 namespace gfx {
 namespace {
 const char kOpenGLFrameworkPath[] =
     "/System/Library/Frameworks/OpenGL.framework/Versions/Current/OpenGL";
 }  // namespace anonymous
 
 void GetAllowedGLImplementations(std::vector<GLImplementation>* impls) {
   impls->push_back(kGLImplementationDesktopGL);
+  impls->push_back(kGLImplementationAppleGL);
   impls->push_back(kGLImplementationOSMesaGL);
 }
 
 bool InitializeGLBindings(GLImplementation implementation) {
   // Prevent reinitialization with a different implementation. Once the gpu
   // unit tests have initialized with kGLImplementationMock, we don't want to
   // later switch to another GL implementation.
   if (GetGLImplementation() != kGLImplementationNone)
     return true;
 
@@ skipping 34 matching lines @@
       }
 
       SetGLGetProcAddressProc(get_proc_address);
       AddGLNativeLibrary(library);
       SetGLImplementation(kGLImplementationOSMesaGL);
 
       InitializeGLBindingsGL();
       InitializeGLBindingsOSMESA();
       break;
     }
-    case kGLImplementationDesktopGL: {
+    case kGLImplementationDesktopGL:
+    case kGLImplementationAppleGL: {
       base::NativeLibrary library = base::LoadNativeLibrary(
           FilePath(kOpenGLFrameworkPath), NULL);
       if (!library) {
         LOG(ERROR) << "OpenGL framework not found";
         return false;
       }
 
       AddGLNativeLibrary(library);
-      SetGLImplementation(kGLImplementationDesktopGL);
+      SetGLImplementation(implementation);
 
       InitializeGLBindingsGL();
       break;
     }
     case kGLImplementationMockGL: {
       SetGLGetProcAddressProc(GetMockGLProcAddress);
       SetGLImplementation(kGLImplementationMockGL);
       InitializeGLBindingsGL();
       break;
     }
     default:
       return false;
   }
 
   return true;
 }
 
 bool InitializeGLExtensionBindings(GLImplementation implementation,
     GLContext* context) {
   switch (implementation) {
     case kGLImplementationOSMesaGL:
       InitializeGLExtensionBindingsGL(context);
       InitializeGLExtensionBindingsOSMESA(context);
       break;
     case kGLImplementationDesktopGL:
+    case kGLImplementationAppleGL:
       InitializeGLExtensionBindingsGL(context);
       break;
     case kGLImplementationMockGL:
       InitializeGLExtensionBindingsGL(context);
       break;
     default:
       return false;
   }
 
   return true;
 }
 
 void InitializeDebugGLBindings() {
   InitializeDebugGLBindingsGL();
   InitializeDebugGLBindingsOSMESA();
 }
 
 void ClearGLBindings() {
   ClearGLBindingsGL();
   ClearGLBindingsOSMESA();
   SetGLImplementation(kGLImplementationNone);
 
   UnloadGLNativeLibraries();
 }
 
 }  // namespace gfx