Implement blacklist's force GPU capability in dual GPU machines.

ui/gl/gl_context_cgl.cc

Index: ui/gl/gl_context_cgl.cc
===================================================================
--- ui/gl/gl_context_cgl.cc	(revision 156195)
+++ ui/gl/gl_context_cgl.cc	(working copy)
@@ -12,6 +12,7 @@
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_implementation.h"
 #include "ui/gl/gl_surface_cgl.h"
+#include "ui/gl/gpu_switching_manager.h"
 
 namespace gfx {
 
@@ -26,6 +27,9 @@
                               GpuPreference gpu_preference) {
   DCHECK(compatible_surface);
 
+  gpu_preference = GpuSwitchingManager::GetInstance()->AdjustGpuPreference(
+      gpu_preference);
+
   GLContextCGL* share_context = share_group() ?
       static_cast<GLContextCGL*>(share_group()->GetContext()) : NULL;
 
@@ -162,15 +166,4 @@
   return gpu_preference_;
 }
 
-void GLContextCGL::ForceUseOfDiscreteGPU() {
-  static CGLPixelFormatObj format = NULL;
-  if (format)
-    return;
-  CGLPixelFormatAttribute attribs[1];
-  attribs[0] = static_cast<CGLPixelFormatAttribute>(0);
-  GLint num_pixel_formats = 0;
-  CGLChoosePixelFormat(attribs, &format, &num_pixel_formats);
-  // format is deliberately leaked.
-}
-
 }  // namespace gfx