MESOS-6406 the master started to actively send frameworks status updates for reregistering agents if the agent:
- has previously been removed by the master for being unreachable or
- is unknown to the master due to the garbage collection of the
unreachable and gone agents in the registry and the master's state.
This is inconsistent with the handling of other master generated updates, e.g,. during reconciliation; we should send the status update state instead.