TpConnection: if already invalidated, don't add interfaces or try to become ready
TpConnection: if already invalidated, don't add interfaces or try to become ready

Reviewed-by: Will Thompson <5822fdda638242a44ccfa68f146ccf6f257c5cbd@collabora.co.uk>

Distrotech/telepathy-glib,Distrotech/telepathy-glib,Distrotech/telepathy-glib,Distrotech/telepathy-glib,Distrotech/telepathy-glib