Remove another unneeded clientContext argument
Remove another unneeded clientContext argument

nmathewson/mixminion,mixminion/mixminion,Javex/mixminion,Javex/mixminion,rxcomm/mixminion,rxcomm/mixminion,nmathewson/mixminion,reezer/mixminion,nmathewson/mixminion,crooks/mixminion,reezer/mixminion,Javex/mixminion,mixminion/mixminion,crooks/mixminion,crooks/mixminion,mixminion/mixminion,rxcomm/mixminion,rxcomm/mixminion,reezer/mixminion,Javex/mixminion,crooks/mixminion,reezer/mixminion,nmathewson/mixminion,mixminion/mixminion