components: Move PrefRegistrySyncable into user_prefs namespace.

chrome/browser/ui/browser_ui_prefs.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_BROWSER_UI_BROWSER_UI_PREFS_H_
 #define CHROME_BROWSER_UI_BROWSER_UI_PREFS_H_
 
 #include <string>
 
 class PrefRegistrySimple;
+class Profile;
+
+namespace user_prefs {
 class PrefRegistrySyncable;
-class Profile;
+}
 
 namespace chrome {
 
 void RegisterBrowserPrefs(PrefRegistrySimple* registry);
-void RegisterBrowserUserPrefs(PrefRegistrySyncable* registry);
+void RegisterBrowserUserPrefs(user_prefs::PrefRegistrySyncable* registry);
 
 // Create a preference dictionary for the provided application name, in the
 // given user profile. This is done only once per application name / per
 // session / per user profile.
 void RegisterAppPrefs(const std::string& app_name, Profile* profile);
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_UI_BROWSER_UI_PREFS_H_