Revert of Revert of ChromeOS NetworkScreenHandler should not call CheckAndResolveLocale on UI thread. (patchs…

chrome/browser/chromeos/login/session/user_session_manager.cc

Index: chrome/browser/chromeos/login/session/user_session_manager.cc
diff --git a/chrome/browser/chromeos/login/session/user_session_manager.cc b/chrome/browser/chromeos/login/session/user_session_manager.cc
index de2ea43d9dff7611163003e0b5b2434c2474cf40..6e2159ce976722978eeef9d85aeaec204eca2838 100644
--- a/chrome/browser/chromeos/login/session/user_session_manager.cc
+++ b/chrome/browser/chromeos/login/session/user_session_manager.cc
@@ -411,7 +411,7 @@
 bool UserSessionManager::RespectLocalePreference(
     Profile* profile,
     const user_manager::User* user,
-    scoped_ptr<locale_util::SwitchLanguageCallback> callback) const {
+    const locale_util::SwitchLanguageCallback& callback) const {
   // TODO(alemate): http://crbug.com/288941 : Respect preferred language list in
   // the Google user profile.
   if (g_browser_process == NULL)
@@ -479,10 +479,8 @@
   // So input methods should be enabled somewhere.
   const bool enable_layouts =
       user_manager::UserManager::Get()->IsLoggedInAsGuest();
-  locale_util::SwitchLanguage(pref_locale,
-                              enable_layouts,
-                              false /* login_layouts_only */,
-                              callback.Pass());
+  locale_util::SwitchLanguage(
+      pref_locale, enable_layouts, false /* login_layouts_only */, callback);
 
   return true;
 }