Initialized the POD type in the `Request` struct.
Initialized the POD type in the `Request` struct.

Previously, the `keepAlive` member was not initialized correctly,
the behavior is undefined if POD types are not correctly
initialized.

Review: https://reviews.apache.org/r/53482/

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