YARN-1522. Fixed a race condition in the test TestApplicationCleanup that was causing it to randomly fail. Contributed by Liyin Liang.
svn merge --ignore-ancestry -c 1554328 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1554329 13f79535-47bb-0310-9956-ffa450edef68