HDFS-5307. Merging change r1530033 from branch-2

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.2@1530126 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5317. Merging change 1530117 from branch-2

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.2@1530127 13f79535-47bb-0310-9956-ffa450edef68
Moving recent bug-fixes to hadoop-2.2.1.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.2@1530130 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5316. Merging change r1530153 from branch-2

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.2@1530154 13f79535-47bb-0310-9956-ffa450edef68