restore
Takes the player back to a memento: applies every setting, opens its queue at its index, goes to its position, then picks the audio and subtitle tracks by language where the new container has them. Ends paused, like every open. A track the memento names and the container lacks leaves the container's own choice in place.
Every setting is checked before anything changes, so a memento this player refuses leaves the player as it was. The volume is clamped to this player's AudioConfig.volumeCeiling instead, because a memento from a player that allowed a boost is still a place to go back to. The settings reach the player before the queue opens, so a source that cannot seek still gets the saved speed; a session that was playing is stopped first for that reason. On such a source the saved position is skipped and PlaybackWarning.StartPositionIgnored says so.
Throws
when the memento's queue is empty, its index is outside it, or one of its settings is outside the range its setter accepts.
when the item at the memento's index cannot be opened.