We already have logic to end all session except the current one if the
current one doesn't have a MediaPeriodId yet. This is assuming that this
only happens after a seek on the app side where the player doesn't have
detailled knowledge about the MediaPeriodIds yet.
Currently this logic isn't triggered if the window we are coming from
doesn't have its MediaPeriodId either as we run into another check that
keeps sessions around until we have a valid windowSequenceNumber.
Swapping both conditions fixes this case without breaking any of the
other known transition scenarios.
Issue: androidx/media#180
PiperOrigin-RevId: 480866465
