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

chrome/browser/chromeos/login/user_manager.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_CHROMEOS_LOGIN_USER_MANAGER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USER_MANAGER_H_
 
 #include <string>
 
 #include "chrome/browser/chromeos/login/user.h"
@@ skipping 181 matching lines @@
   // http://crbug.com/230852
   virtual const User* GetLoggedInUser() const = 0;
   virtual User* GetLoggedInUser() = 0;
 
   // Returns the logged-in user that is currently active within this session.
   // There could be multiple users logged in at the the same but for now
   // we support only one of them being active.
   virtual const User* GetActiveUser() const = 0;
   virtual User* GetActiveUser() = 0;
 
+  // Returns primary user. There could be multiple users logged in at the
+  // same time, but only the first one defines locale and other login session
+  // parameters.
+  virtual const User* GetPrimaryUser() const = 0;
+
   // Saves user's oauth token status in local state preferences.
   virtual void SaveUserOAuthStatus(
       const std::string& username,
       User::OAuthTokenStatus oauth_token_status) = 0;
 
   // Saves user's displayed name in local state preferences.
   // Ignored If there is no such user.
   virtual void SaveUserDisplayName(const std::string& username,
                                    const string16& display_name) = 0;
 
+  // Updates data upon User Account download.
+  virtual void UpdateUserAccountData(const std::string& username,
+                                     const string16& display_name,
+                                     const std::string& locale) = 0;
+
   // Returns the display name for user |username| if it is known (was
   // previously set by a |SaveUserDisplayName| call).
   // Otherwise, returns an empty string.
   virtual string16 GetUserDisplayName(
       const std::string& username) const = 0;
 
   // Saves user's displayed (non-canonical) email in local state preferences.
   // Ignored If there is no such user.
   virtual void SaveUserDisplayEmail(const std::string& username,
                                     const std::string& display_email) = 0;
@@ skipping 167 matching lines @@
   ScopedTestUserManager();
   ~ScopedTestUserManager();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ScopedTestUserManager);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USER_MANAGER_H_