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ab6b0f6e10
A bug was introduced because it was unclear that button state creation and listener registration were not an atomic operation. This happens because the `LaunchedEffect` which starts the listen-to-Player-Events coroutine can be pre-empted with other side effects, including the ones that change something in the Player. `remember*State` functions create some button state object and initialise it with the correct fresh values pulled out of the Player. The subscription to Player events with a registration of a Listener(via `*ButtonState.observe()`) is not immediate. It *returns* immediately, but is instead scheduled to happen *later*, although within the same Handler message. Other LaunchedEffects could have been scheduled earlier and could take place between the button state creation and listener subscription. This is not a problem if no changes to the player happen, but if we miss the *relevant* player events, we might end up with a UI that is out of sync with reality (e.g. button enabled/disabled when it should be flipped, icons toggled the wrong way). The way to fix this is to pull the latest values out of the Player on demand upon starting to listen to Player events. PiperOrigin-RevId: 750183793