gabble_roster_dup_states: don't assume the 'out' arguments are non-NULL
gabble_roster_dup_states: don't assume the 'out' arguments are non-NULL

jku/telepathy-gabble,Ziemin/telepathy-gabble,mlundblad/telepathy-gabble,jku/telepathy-gabble,mlundblad/telepathy-gabble,jku/telepathy-gabble,Ziemin/telepathy-gabble,Ziemin/telepathy-gabble,Ziemin/telepathy-gabble,mlundblad/telepathy-gabble