mixer-control: Rely on stream-id on device for cardless devices
requested to merge jadahl/libgnome-volume-control:wip/dont-match-network-streams-when-syncing into master
Some devices don't have a card to match against, (e.g. network sinks), which would make 'match_stream_with_devices()' get confused and log warnings about missing card devices when trying to match streams with devices.
Avoid this by marking a stream as 'in-possession' if there was already a device with the stream ID set to it.
This fixes warning like
(gnome-shell:3521215): Gvc-CRITICAL **: 10:57:07.155: gvc_mixer_card_get_index: assertion 'GVC_IS_MIXER_CARD (card)' failed
Disclaimer: I don't know if this is the correct way; i.e. if there were "old" devices that need to update some how. Would gladly try to fix the matching to be more correct if this isn't the proper solution.