$differenceEngine: DifferenceEngine object
&$markAsPatrolledLink: The "mark as patrolled" link HTML (string)
$rcid: Recent change ID (rc_id) for this change (int)
-$token: Patrol token; $rcid is used in generating this variable
'DifferenceEngineMarkPatrolledRCID': Allows extensions to possibly change the rcid parameter.
For example the rcid might be set to zero due to the user being the same as the