We'll need this for the upcoming change to add an upper bound on drain lifetime.

Since we're doing a cluster replacement anyway for closing idle
drains, we might as well get this record change in while we're at it
so the next upgrade can be a live one.
Re-use existing timestamp.
Missed adding this to the HTTP side.
HTTP drains have close_if_idle returning the fsm state.
Merge branch 'connect-time-field'