YARN-2993. Several fixes (missing acl check, error log msg ...) and some refinement in AdminService. (Contributed by Yi Liu)
(cherry picked from commit 40ee4bff65b2bfdabfd16ee7d9be3382a0476565)
YARN-2992. ZKRMStateStore crashes due to session expiry. Contributed by Karthik Kambatla
(cherry picked from commit 1454efe5d4fe4214ec5ef9142d55dbeca7dab953)
Merge remote-tracking branch 'remotes/origin/branch-2' into branch-2