YARN-2374. Fixed TestDistributedShell#testDSShell failure due to hostname dismatch. Contributed by Varun Vasudev

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1616302 13f79535-47bb-0310-9956-ffa450edef68
HDFS-6791. A block could remain under replicated if all of its replicas are on decommissioned nodes. Contributed by Ming Ma.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1616306 13f79535-47bb-0310-9956-ffa450edef68