Revert "Remove webkit_glue::BuildUserAgent(), change the contract in webkit_glue"

chrome_frame/renderer_glue.cc

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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 "webkit/glue/user_agent.h"
 #include "webkit/glue/webkit_glue.h"
 
 #include "chrome/common/chrome_version_info.h"
 
 class GURL;
 
 bool IsPluginProcess() {
   return false;
 }
+
+namespace webkit_glue {
+
+std::string BuildUserAgent(bool mimic_windows) {
+  chrome::VersionInfo version_info;
+  std::string product("Chrome/");
+  product += version_info.is_valid() ? version_info.Version()
+                                     : "0.0.0.0";
+  return webkit_glue::BuildUserAgentHelper(mimic_windows, product);
+}
+
+}  // end namespace webkit_glue