Updated MesosZooKeeperTest to avoid side effects.
Updated MesosZooKeeperTest to avoid side effects.

Review: https://reviews.apache.org/r/36899

verizonlabs/mesos,reneploetz/mesos,yuquanshan/customizedMesos,jpeach/mesos,Gilbert88/mesos,Aman-Jain-14/customizedMesos,kaysoky/mesos,neilconway/mesos,yuquanshan/customizedMesos,gsantovena/mesos,Aman-Jain-14/customizedMesos,kaysoky/mesos,jpeach/mesos,craimbert/mesos,yuquanshan/customizedMesos,gsantovena/mesos,zmalik/mesos,gsantovena/mesos,Gilbert88/mesos,dforsyth/mesos,chhsia0/mesos,abudnik/mesos,andschwa/mesos,andschwa/mesos,andschwa/mesos,Gilbert88/mesos,jpeach/mesos,craimbert/mesos,chhsia0/mesos,craimbert/mesos,chhsia0/mesos,zmalik/mesos,Gilbert88/mesos,Aman-Jain-14/customizedMesos,yuquanshan/customizedMesos,dforsyth/mesos,gsantovena/mesos,zmalik/mesos,verizonlabs/mesos,asamerh4/mesos,reneploetz/mesos,asamerh4/mesos,zmalik/mesos,Aman-Jain-14/customizedMesos,neilconway/mesos,craimbert/mesos,reneploetz/mesos,neilconway/mesos,verizonlabs/mesos,kaysoky/mesos,verizonlabs/mesos,asamerh4/mesos,yuquanshan/customizedMesos,andschwa/mesos,dforsyth/mesos,asamerh4/mesos,jpeach/mesos,reneploetz/mesos,Aman-Jain-14/customizedMesos,chhsia0/mesos,dforsyth/mesos,verizonlabs/mesos,craimbert/mesos,dforsyth/mesos,reneploetz/mesos,chhsia0/mesos,kaysoky/mesos,gsantovena/mesos,abudnik/mesos,yuquanshan/customizedMesos,andschwa/mesos,craimbert/mesos,dforsyth/mesos,Gilbert88/mesos,zmalik/mesos,reneploetz/mesos,chhsia0/mesos,dforsyth/mesos,kaysoky/mesos,neilconway/mesos,abudnik/mesos,verizonlabs/mesos,jpeach/mesos,Aman-Jain-14/customizedMesos,gsantovena/mesos,kaysoky/mesos,abudnik/mesos,Gilbert88/mesos,neilconway/mesos,Aman-Jain-14/customizedMesos,kaysoky/mesos,jpeach/mesos,chhsia0/mesos,yuquanshan/customizedMesos,abudnik/mesos,asamerh4/mesos,neilconway/mesos,gsantovena/mesos,abudnik/mesos,reneploetz/mesos,neilconway/mesos,andschwa/mesos,verizonlabs/mesos,zmalik/mesos,asamerh4/mesos,asamerh4/mesos,craimbert/mesos,abudnik/mesos,jpeach/mesos,andschwa/mesos,zmalik/mesos,Gilbert88/mesos