_mcd_dispatcher_enter_state_machine: don't short-cut to running clients if there are no filters
_mcd_dispatcher_enter_state_machine: don't short-cut to running clients if there are no filters

If there are no filters, mcd_dispatcher_context_proceed will run the
clients anyway, so we might as well reduce the number of code paths.

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