Updated hierarchical allocator tests to use -> operator.
Updated hierarchical allocator tests to use -> operator.

Review: https://reviews.apache.org/r/55824

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