Move BrowserThread to content namespace.

content/browser/file_system/browser_file_system_helper.cc

 // Copyright (c) 2011 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 "content/browser/file_system/browser_file_system_helper.h"
 
 #include "base/command_line.h"
 #include "base/file_path.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/common/content_switches.h"
 #include "webkit/quota/quota_manager.h"
 
+using content::BrowserThread;
+
 scoped_refptr<fileapi::FileSystemContext> CreateFileSystemContext(
         const FilePath& profile_path, bool is_incognito,
         quota::SpecialStoragePolicy* special_storage_policy,
         quota::QuotaManagerProxy* quota_manager_proxy) {
   return new fileapi::FileSystemContext(
       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE),
       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO),
       special_storage_policy,
       quota_manager_proxy,
       profile_path,
       is_incognito,
       CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kAllowFileAccessFromFiles),
       NULL);
 }