UC-125 Fix fatal error on FBConnect

This is the only instantiation that does not check for user prior to passing it down to FBConnectUser

Ticket: https://wikia-inc.atlassian.net/browse/UC-125
You could use the ```noname``` string here ('You have not specified a valid username.') which comes from the same file as ```wrongpassword```, ```languages/messages/MessagesEn.php```