Remove windows/mac/ios specific code from //ui

ui/gl/scoped_cgl.h

-// Copyright 2014 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_SCOPED_CGL_H_
-#define UI_GL_SCOPED_CGL_H_
-
-#include <OpenGL/OpenGL.h>
-
-#include "base/mac/scoped_typeref.h"
-#include "ui/gl/gl_export.h"
-
-namespace base {
-
-template<>
-struct ScopedTypeRefTraits<CGLContextObj> {
-  static void Retain(CGLContextObj object) {
-    CGLRetainContext(object);
-  }
-  static void Release(CGLContextObj object) {
-    CGLReleaseContext(object);
-  }
-};
-
-template<>
-struct ScopedTypeRefTraits<CGLPixelFormatObj> {
-  static void Retain(CGLPixelFormatObj object) {
-    CGLRetainPixelFormat(object);
-  }
-  static void Release(CGLPixelFormatObj object) {
-    CGLReleasePixelFormat(object);
-  }
-};
-
-}  // namespace base
-
-namespace gfx {
-
-class GL_EXPORT ScopedCGLSetCurrentContext {
- public:
-  explicit ScopedCGLSetCurrentContext(CGLContextObj context);
-  ~ScopedCGLSetCurrentContext();
- private:
-  // Note that if a context is destroyed when it is current, then the current
-  // context is changed to NULL. Take out a reference on |previous_context_| to
-  // preserve this behavior (when this falls out of scope, |previous_context_|
-  // will be made current, then released, so NULL will be current if that
-  // release destroys the context).
-  base::ScopedTypeRef<CGLContextObj> previous_context_;
-
-  DISALLOW_COPY_AND_ASSIGN(ScopedCGLSetCurrentContext);
-};
-
-}  // namespace gfx
-
-#endif  // UI_GL_SCOPED_CGL_H_