Patched glog to compile demangle.cc with clang.
Patched glog to compile demangle.cc with clang.

Review: https://reviews.apache.org/r/18307

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