HADOOP-10754. Merging change r1605924 from trunk to branch-2.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1605926 13f79535-47bb-0310-9956-ffa450edef68
HDFS-6572. Merging change r1605928 from trunk to branch-2.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1605930 13f79535-47bb-0310-9956-ffa450edef68