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

ui/gfx/gl/gl_surface_cgl.cc

Index: ui/gfx/gl/gl_surface_cgl.cc
===================================================================
--- ui/gfx/gl/gl_surface_cgl.cc	(revision 113194)
+++ ui/gfx/gl/gl_surface_cgl.cc	(working copy)
@@ -4,11 +4,14 @@
 
 #include "ui/gfx/gl/gl_surface_cgl.h"
 
+#include <OpenGL/CGLRenderers.h>
+
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/mac/mac_util.h"
 #include "ui/gfx/gl/gl_bindings.h"
 #include "ui/gfx/gl/gl_context.h"
+#include "ui/gfx/gl/gl_implementation.h"
 
 namespace gfx {
 
@@ -36,6 +39,11 @@
     // format selection.
     attribs.push_back(kCGLPFAAllowOfflineRenderers);
   }
+  if (GetGLImplementation() == kGLImplementationAppleGL) {
+    attribs.push_back(kCGLPFARendererID);
+    attribs.push_back(static_cast<CGLPixelFormatAttribute>(
+      kCGLRendererGenericFloatID));
+  }
   attribs.push_back(static_cast<CGLPixelFormatAttribute>(0));
 
   CGLPixelFormatObj format;