Removed pre-C++11 codepath in Mesos.
Removed pre-C++11 codepath in Mesos.

Review: https://reviews.apache.org/r/33562

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