Refactor GL bindings so there is no global GLApi or DriverGL.

ui/gl/gl_context_glx.cc

 // 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.
 
 #include "ui/gl/gl_context_glx.h"
 
 extern "C" {
 #include <X11/Xlib.h>
 }
 #include <memory>
@@ skipping 225 matching lines @@
       display_,
       reinterpret_cast<GLXDrawable>(surface->GetHandle()),
       reinterpret_cast<GLXDrawable>(surface->GetHandle()),
       static_cast<GLXContext>(context_))) {
     LOG(ERROR) << "Couldn't make context current with X drawable.";
     Destroy();
     return false;
   }
 
   // Set this as soon as the context is current, since we might call into GL.
-  SetRealGLApi();
+  BindGLApi();
 
   SetCurrent(surface);
   InitializeDynamicBindings();
 
   if (!surface->OnMakeCurrent(this)) {
     LOG(ERROR) << "Could not make current.";
     Destroy();
     return false;
   }
 
@@ skipping 67 matching lines @@
 
 bool GLContextGLX::WasAllocatedUsingRobustnessExtension() {
   return GLSurfaceGLX::IsCreateContextRobustnessSupported();
 }
 
 GLContextGLX::~GLContextGLX() {
   Destroy();
 }
 
 }  // namespace gl