Confusing, I know. When a coordinator is created, a task is scheduled at transactionLifetimeLimitSeconds (the time after which an unprepared transaction is allowed to be reaped) in the future to "cancel" the commit coordination (i.e., allow the coordinator to be destroyed so that it does not hang around in memory forever). The "cancel" is a no-op if the coordinator has already received the participant list by the time the task runs.

This ticket is to store a handle to the task inside the coordinator, so that the coordinator can cancel the "cancel" task on receiving the participant list.