Fixed user cgroup failing test on centos 7.
Fixed user cgroup failing test on centos 7.

Review: https://reviews.apache.org/r/37863

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