Move --user-agent overriding logic from chrome into content.

chrome/common/chrome_content_client.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 CHROME_COMMON_CHROME_CONTENT_CLIENT_H_
 #define CHROME_COMMON_CHROME_CONTENT_CLIENT_H_
 #pragma once
 
 #include "base/compiler_specific.h"
 #include "content/public/common/content_client.h"
 
 namespace chrome {
 
 class ChromeContentClient : public content::ContentClient {
  public:
   static const char* const kPDFPluginName;
   static const char* const kNaClPluginName;
   static const char* const kNaClOldPluginName;
 
   virtual void SetActiveURL(const GURL& url) OVERRIDE;
   virtual void SetGpuInfo(const content::GPUInfo& gpu_info) OVERRIDE;
   virtual void AddPepperPlugins(
       std::vector<content::PepperPluginInfo>* plugins) OVERRIDE;
   virtual void AddNPAPIPlugins(
       webkit::npapi::PluginList* plugin_list) OVERRIDE;
   virtual bool HasWebUIScheme(const GURL& url) const OVERRIDE;
   virtual bool CanHandleWhileSwappedOut(const IPC::Message& msg) OVERRIDE;
-  virtual std::string GetUserAgent(bool* overriding) const OVERRIDE;
+  virtual std::string GetUserAgent() const OVERRIDE;
   virtual string16 GetLocalizedString(int message_id) const OVERRIDE;
   virtual base::StringPiece GetDataResource(int resource_id) const OVERRIDE;
 
 #if defined(OS_WIN)
   virtual bool SandboxPlugin(CommandLine* command_line,
                              sandbox::TargetPolicy* policy) OVERRIDE;
 #endif
 
 #if defined(OS_MACOSX)
   virtual bool GetSandboxProfileForSandboxType(
       int sandbox_type,
       int* sandbox_profile_resource_id) const OVERRIDE;
 #endif
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_COMMON_CHROME_CONTENT_CLIENT_H_