YARN-1251. TestDistributedShell#TestDSShell failed with timeout. Contributed by Xuan Gong.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1529369 13f79535-47bb-0310-9956-ffa450edef68
YARN-1167. Fixed Distributed Shell to not incorrectly show empty hostname on RM UI. Contributed by Xuan Gong.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1529376 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk-gd
Merge remote branch 'origin/trunk-gd' into fb-HDFS-4312-trunk-gd