Part of the changes introduced through SERVER-112658 implied transferring the management of "Sharding" subsystems to a dedicated ReplicaSetAwareService; this introduced the need of having access to an OperationContext object during the execution of an onStepDown() callback: today this gets retrieved through the cc() call, whose usage is discouraged.

As a cleaner alternative, the signature of ReplicaSetAware::onStepDown() could be modified to include such a parameter.