[cros] Use ScheduleSavePersistentPrefs instead of SavePersistentPrefs.

chrome/browser/chromeos/login/language_switch_menu.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 "chrome/browser/chromeos/login/language_switch_menu.h"
 
 #include "base/i18n/rtl.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/browser_process.h"
@@ skipping 104 matching lines @@
     LoadFontsForCurrentLocale();
 
     // The following line does not seem to affect locale anyhow. Maybe in
     // future..
     g_browser_process->SetApplicationLocale(locale);
 
     // Force preferences save, otherwise they won't be saved on
     // shutdown from login screen. http://crosbug.com/20747
     PrefService* prefs = g_browser_process->local_state();
     prefs->SetString(prefs::kApplicationLocale, locale);
-    prefs->SavePersistentPrefs();
+    prefs->ScheduleSavePersistentPrefs();
 
     return true;
   }
   return false;
 }
 
 // static
 void LanguageSwitchMenu::LoadFontsForCurrentLocale() {
 #if defined(TOOLKIT_USES_GTK)
   std::string gtkrc = l10n_util::GetStringUTF8(IDS_LOCALE_GTKRC);
@@ skipping 65 matching lines @@
   // Here, we should enable keyboard layouts associated with the locale so
   // that users can use those keyboard layouts on the login screen.
   SwitchLanguageAndEnableKeyboardLayouts(locale);
   InitLanguageMenu();
 
   // Update all view hierarchies that the locale has changed.
   views::Widget::NotifyLocaleChanged();
 }
 
 }  // namespace chromeos