In dispose() unsubscribe again after being sure that all pending messages (incl ev. pending subscriptions) have been cancelled.
In dispose() unsubscribe again after being sure that all pending
messages (incl ev. pending subscriptions) have been cancelled.

Signed-off-by: Sven Neumann <082b688ad1df15a85cd4e0d35bae9067e5474d70@raumfeld.com>

ZachGoldberg/gupnp-gi,GNOME/gupnp,GNOME/gupnp,GNOME/gupnp,ZachGoldberg/gupnp-gi,ZachGoldberg/gupnp-gi,GNOME/gupnp