Update the allocator unit tests to reflect MULTI_ROLE support.
Update the allocator unit tests to reflect MULTI_ROLE support.

Review: https://reviews.apache.org/r/55967

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