svn merge -c 1454460. Merging from trunk to branch-2 to fix HDFS-4567.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1454468 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4571. WebHDFS should not set the service hostname on the server side. (tucu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1454476 13f79535-47bb-0310-9956-ffa450edef68
svn merge -c 1454517 Merging from trunk to branch-2 to fix HDFS-4577.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1454519 13f79535-47bb-0310-9956-ffa450edef68