McdDispatcher: when selecting a Handler for requested channels, use their real properties if possible
McdDispatcher: when selecting a Handler for requested channels, use their real properties if possible

When we have the properties of the actual channel, we should use those,
rather than relying on the incomplete set of properties that were
requested.

freedesktop-unofficial-mirror/telepathy__telepathy-mission-control,freedesktop-unofficial-mirror/telepathy__telepathy-mission-control,freedesktop-unofficial-mirror/telepathy__telepathy-mission-control,freedesktop-unofficial-mirror/telepathy__telepathy-mission-control