Fix gl context change on dropping a texture

ui/gfx/gl/scoped_make_current.h

 // 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.
 
 #ifndef UI_GFX_GL_SCOPED_MAKE_CURRENT_H_
 #define UI_GFX_GL_SCOPED_MAKE_CURRENT_H_
 #pragma once
 
+#include "base/memory/ref_counted.h"
 #include "ui/gfx/gl/gl_context.h"
 #include "ui/gfx/gl/gl_surface.h"
 
 namespace gfx {
 
-class GL_EXPORT ScopedMakeCurrent {
+class GL_EXPORT ScopedMakeCurrent : public base::RefCounted<ScopedMakeCurrent> {

[sky, 2011/10/31 20:44:45]

Having a RAII object be ref counted breaks the model of how one uses an RAII
object. I would rather either expose the GLContext/GLSurface, or rename
ScopedMakeCurrent to GetScopedMakeCurrent and have it take a pointer to
ScopedMakeCurrent (and change ScopedMakeCurrent to have an empty constructor).

  public:
   explicit ScopedMakeCurrent(GLContext* context, GLSurface* surface);
   ~ScopedMakeCurrent();
 
   bool Succeeded();
 
  private:
   scoped_refptr<GLContext> previous_context_;
   scoped_refptr<GLSurface> previous_surface_;
   scoped_refptr<GLContext> context_;
   scoped_refptr<GLSurface> surface_;
   bool succeeded_;
+
+  friend class base::RefCounted<ScopedMakeCurrent>;
   DISALLOW_COPY_AND_ASSIGN(ScopedMakeCurrent);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_GL_SCOPED_MAKE_CURRENT_H_