Fixed Mesos protobuf library detection.
Fixed Mesos protobuf library detection.

Review: https://reviews.apache.org/r/39775

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