Committing or discarding the keys of a password change that failed midway trusted the client to have just logged in. An older session could discard keys for a password that had been set, leaving them unwrappable. Both now require the token's auth_time to be after the keys were staged, and return login_required otherwise. Refreshed tokens keep the auth_time of the original login.
Discarding still waits until the password change can no longer be running.
