HADOOP-10029. Merging change 1531126 from branch-2.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.2@1531129 13f79535-47bb-0310-9956-ffa450edef68
YARN-1265. Fair Scheduler chokes on unhealthy node reconnect (Sandy Ryza)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.2@1531148 13f79535-47bb-0310-9956-ffa450edef68