Revert 158076 - Implement blacklist's force GPU capability in dual GPU machines.

ui/gl/gl_context_cgl.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.
 
 #ifndef UI_GL_GL_CONTEXT_CGL_H_
 #define UI_GL_GL_CONTEXT_CGL_H_
 
 #include <OpenGL/CGLTypes.h>
 
 #include "base/memory/scoped_generic_obj.h"
@@ skipping 20 matching lines @@
   virtual bool GetTotalGpuMemory(size_t* bytes) OVERRIDE;
 
   // Helper for dual-GPU support on systems where this is necessary
   // for stability reasons.
   static void ForceUseOfDiscreteGPU();
 
  protected:
   virtual ~GLContextCGL();
 
  private:
+  // Expose ForceUseOfDiscreteGPU only to GLContext implementation.
+  friend class GLContext;
+
   GpuPreference GetGpuPreference();
 
+  // Helper for dual-GPU support on systems where this is necessary
+  // for stability reasons.
+  static void ForceUseOfDiscreteGPU();
+
   void* context_;
   GpuPreference gpu_preference_;
 
   CGLPixelFormatObj discrete_pixelformat_;
 
   DISALLOW_COPY_AND_ASSIGN(GLContextCGL);
 };
 
 class ScopedCGLDestroyRendererInfo {
  public:
   void operator()(CGLRendererInfoObj x) const;
 };
 
 typedef ScopedGenericObj<CGLRendererInfoObj, ScopedCGLDestroyRendererInfo>
     ScopedCGLRendererInfoObj;
 
 }  // namespace gfx
 
 #endif  // UI_GL_GL_CONTEXT_CGL_H_