486a7818 'Fix poll hang in os-test basic/poll': the fork still had
unregister_queue as a //TODO stub, so closed event queues leaked their registry
entries (the poll-hang class). Merged with RedBear's ref-counted queue-close
logic: keep the kdup dec_ref/is_last handling, and call unregister_queue(id,
token) to clean the registry when the last fd closes. Event-timeout handling was
already present as RedBear's own impl.
vasilito
5fdbbe82e9