Restrict usage of mesa headers to targets that really need them

ui/gl/gl_surface_osmesa.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_SURFACE_OSMESA_H_
 #define UI_GL_GL_SURFACE_OSMESA_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "ui/gfx/size.h"
 #include "ui/gl/gl_surface.h"
 
 namespace gfx {
 
+enum OSMesaSurfaceFormat { OSMesaSurfaceFormatBGRA, OSMesaSurfaceFormatRGBA };
+
 // A surface that the Mesa software renderer draws to. This is actually just a
 // buffer in system memory. GetHandle returns a pointer to the buffer. These
 // surfaces can be resized and resizing preserves the contents.
 class GL_EXPORT GLSurfaceOSMesa : public GLSurface {
  public:
-  GLSurfaceOSMesa(unsigned format, const gfx::Size& size);
+  GLSurfaceOSMesa(OSMesaSurfaceFormat format, const gfx::Size& size);
 
   // Implement GLSurface.
   virtual bool Initialize() OVERRIDE;
   virtual void Destroy() OVERRIDE;
   virtual bool Resize(const gfx::Size& new_size) OVERRIDE;
   virtual bool IsOffscreen() OVERRIDE;
   virtual bool SwapBuffers() OVERRIDE;
   virtual gfx::Size GetSize() OVERRIDE;
   virtual void* GetHandle() OVERRIDE;
   virtual unsigned GetFormat() OVERRIDE;
@@ skipping 22 matching lines @@
  protected:
   virtual ~GLSurfaceOSMesaHeadless();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(GLSurfaceOSMesaHeadless);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GL_GL_SURFACE_OSMESA_H_