svn merge -c 1490803 Merging from trunk to branch-2 to fix HDFS-4832.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1490805 13f79535-47bb-0310-9956-ffa450edef68
YARN-686. Flatten NodeReport. (sandyr via tucu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1490828 13f79535-47bb-0310-9956-ffa450edef68