Change X11 error handler override to allow easy X11 error checking.

ui/gfx/gl/gl_bindings.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.
 
 // Includes the platform independent and platform dependent GL headers.
 // Only include this in cc files. It pulls in system headers, including
 // the X11 headers on linux, which define all kinds of macros that are
 // liable to cause conflicts.
 
 #ifndef UI_GFX_GL_GL_BINDINGS_H_
 #define UI_GFX_GL_GL_BINDINGS_H_
 #pragma once
 
 #include <GL/gl.h>
 #include <GL/glext.h>
 
 #include "build/build_config.h"
 #include "base/logging.h"
 #include "ui/gfx/gl/gl_export.h"
 
 // The standard OpenGL native extension headers are also included.
 #if defined(OS_WIN)
 #include <GL/wglext.h>
 #elif defined(OS_MACOSX)
 #include <OpenGL/OpenGL.h>
 #elif defined(USE_X11)
 #include <GL/glx.h>
 #include <GL/glxext.h>
-
-// Undefine some macros defined by X headers. This is why this file should only
-// be included in .cc files.
-#undef Bool
-#undef None
-#undef Status
 #endif
 
 #if defined(OS_WIN)
 #define GL_BINDING_CALL WINAPI
 #else
 #define GL_BINDING_CALL
 #endif
 
 #define GL_SERVICE_LOG(args) DLOG(INFO) << args;
 
@@ skipping 48 matching lines @@
 #endif
 
 namespace gfx {
 
 // Find an entry point to the mock GL implementation.
 void* GL_BINDING_CALL GetMockGLProcAddress(const char* name);
 
 }  // namespace gfx
 
 #endif  // UI_GFX_GL_GL_BINDINGS_H_