Project: mesos
Issue MESOS-1410: Keep terminal unacknowledged tasks in the master's state.
Once we are sending acknowledgments through the master as per MESOS-1409, we need to keep terminal tasks that are *unacknowledged* in the Master's memory. This will allow us to identify these tasks to frameworks when we haven't yet forwarded them an update. Without this, we're susceptible to MESOS-1389.
Story points: 5