Respect the disabled extension list during binding initialization.

ui/gl/gl_glx_api_implementation.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_GLX_API_IMPLEMENTATION_H_
 #define UI_GL_GL_GLX_API_IMPLEMENTATION_H_
 
 #include "base/compiler_specific.h"
 #include "gl_bindings.h"
 #include "ui/gl/gl_export.h"
@@ skipping 21 matching lines @@
   void InitializeBase(DriverGLX* driver);
 
   DriverGLX* driver_;
 };
 
 class GL_EXPORT RealGLXApi : public GLXApiBase {
  public:
   RealGLXApi();
   ~RealGLXApi() override;
   void Initialize(DriverGLX* driver);
+  std::set<std::string> GetEnabledExtensions() const;
 };
 
 // Inserts a TRACE for every GLX call.
 class GL_EXPORT TraceGLXApi : public GLXApi {
  public:
   TraceGLXApi(GLXApi* glx_api) : glx_api_(glx_api) { }
   ~TraceGLXApi() override;
 
   // Include the auto-generated part of this class. We split this because
   // it means we can easily edit the non-auto generated parts right here in
   // this file instead of having to edit some template or the code generator.
   #include "gl_bindings_api_autogen_glx.h"
 
  private:
   GLXApi* glx_api_;
 };
 
 }  // namespace gfx
 
 #endif  // UI_GL_GL_GLX_API_IMPLEMENTATION_H_