HADOOP-9264. Merging change r1494705 from branch-2 to branch-2.1-beta.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.1-beta@1494707 13f79535-47bb-0310-9956-ffa450edef68
Clean up an IPC error message. Contributed by Aaron T. Myers.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.1-beta@1494710 13f79535-47bb-0310-9956-ffa450edef68
YARN-597. Merging change r1494713 from branch-2 to branch-2.1-beta.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.1-beta@1494716 13f79535-47bb-0310-9956-ffa450edef68
YARN-852. Merging change r1494735 from branch-2 to branch-2.1-beta.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.1-beta@1494737 13f79535-47bb-0310-9956-ffa450edef68