Minor bugfix for timekeeper

These changes are already part of the next big patch for recovery.
Committing these separately to unblock QE.

Change-Id: I468638a16028c55222f52ff7f6677713195a5f07
Reviewed-on: http://review.couchbase.org/41606
Reviewed-by: John Liang <johliang00@gmail.com>
Reviewed-by: Deepkaran Salooja <deepkaran.couchbase@gmail.com>
Tested-by: Deepkaran Salooja <deepkaran.couchbase@gmail.com>