Some Player implementations have no playlist capability but can still
set a MediaItem for playback. Examples are a MediaController connected
to a legacy MediaSession, ExoPlayer up to 2.12 or MediaPlayer.
To indicate this capability, we need an allowed command in addition
to COMMAND_CHANGE_MEDIA_ITEMS that just allows to set a single item
that replaces everything that is currently played.
#minor-release
PiperOrigin-RevId: 453879626
(cherry picked from commit 5333c67d08)
Before this change we checked whether the playback state and playWhenReady have changed when the state from the cast device arrived. If we detected such a change we called the listener callback `onIsPlayingChanged`. However, in the case when `setPlayWhenReady(boolean)` is called on 'CastPlayer', we mask the change in `playWhenReady`, then send the play/pause request to the cast device and when the state from the cast device arrives we never detect a change because we have already masked `playWhenReady`.
This change now moves the check for `isPlaying` to the same place where the state and playWhenReady is updated, so we call the `onIsPlayingChanged` callback in either case, when masking or when a changed state from the server arrives.
Issue: google/ExoPlayer#9792
PiperOrigin-RevId: 418483509
