Starts a round, or drops an unforced start while one is running.
A forced start takes over the running round. The new number shuts out its late answers, and its own close with them.
The round state to read and update in place.
Whether to start even when a round is already running.
The new round's number, or null when the start was dropped.
Starts a round, or drops an unforced start while one is running.
A forced start takes over the running round. The new number shuts out its late answers, and its own close with them.