Fix when user_id is nil (anonymous).
Fix when user_id is nil (anonymous).

nanaya/moebooru,euank/moebooru-thin,euank/moebooru-thin,moebooru/moebooru,moebooru/moebooru,nanaya/moebooru,nanaya/moebooru,moebooru/moebooru,nanaya/moebooru,nanaya/moebooru,euank/moebooru-thin,moebooru/moebooru,moebooru/moebooru,euank/moebooru-thin,euank/moebooru-thin