In some cases, the ExoPlayer immediately transitions to `STATE_IDLE` or `STATE_ENDED` on application thread, while `isLoading` can still remain as `true` before it is finally updated from playback thread.
Issue: androidx/media#2133
#cherrypick
PiperOrigin-RevId: 728724157
(cherry picked from commit daf8f9ff584e52128b94b4b08a1e9cf7ba94dee2)