If user profile doesn't contain language setting, default to his Google account settings.

chrome/browser/chromeos/login/fake_user_manager.h

 // Copyright 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_LOGIN_FAKE_USER_MANAGER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_FAKE_USER_MANAGER_H_
 
 #include <string>
 
 #include "chrome/browser/chromeos/login/user.h"
@@ skipping 20 matching lines @@
 
   // Set the user as logged in.
   virtual void UserLoggedIn(const std::string& email,
                             const std::string& username_hash,
                             bool browser_restart) OVERRIDE;
 
   virtual const User* GetActiveUser() const OVERRIDE;
   virtual User* GetActiveUser() OVERRIDE;
   virtual void SaveUserDisplayName(const std::string& username,
       const string16& display_name) OVERRIDE;
+  virtual void UpdateUserAccountData(const std::string&, const string16&,
+                                     const std::string&) OVERRIDE;
 
   // Not implemented.
   virtual void Shutdown() OVERRIDE {}
   virtual UserImageManager* GetUserImageManager() OVERRIDE;
   virtual const UserList& GetLRULoggedInUsers() OVERRIDE;
   virtual UserList GetUnlockUsers() const OVERRIDE;
   virtual const std::string& GetOwnerEmail() OVERRIDE;
   virtual void SwitchActiveUser(const std::string& email) OVERRIDE {}
   virtual void SessionStarted() OVERRIDE {}
   virtual void RestoreActiveSessions() OVERRIDE {}
@@ skipping 77 matching lines @@
   UserList user_list_;
   UserList logged_in_users_;
   std::string owner_email_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeUserManager);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_FAKE_USER_MANAGER_H_