jschoubben
16e4e61a0f
Review of 2ee7589: a node that sleeps after running F healthy kept its stale
have as a witness, so F stayed unheld while it failed on the online nodes; and a
failed-alone condition was never cleared once its node left the module.
A witness must now be online by the watchman's presence. F failing on a second
node is no longer one node's failure: the hold and the set-back stand (ADR 0557
version 6, §2). A remembered failed-alone key whose node is no longer one of the
module's nodes is cleared once; the first pass after a start clears it for every
node the presence bucket knows, for a module with a failed have.