Take GL version and extensions correctly into account when binding functions

ui/gl/gl_context_mock_version.cc

+// Copyright (c) 2013 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_mock_version.h"
+#include "ui/gl/gl_version_info.h"
+
+namespace gfx {
+
+GLContextMockVersion::GLContextMockVersion(const char* version_str)
+    : GLContextStub()
+    , version_str_(version_str)
+{}
+
+std::string GLContextMockVersion::GetGLVersion() {
+    return std::string(version_str_);
+}
+
+GLContextMockVersion::~GLContextMockVersion() {}
+
+}  // namespace gfx