channelspecific example room: implement TpExportableChannel
channelspecific example room: implement TpExportableChannel

Also accept 'initiator-handle' as a construct-time property.

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