YARN-2117. Fixed the issue that secret file reader is potentially not closed in TimelineAuthenticationFilterInitializer. Contributed by Chen He.
svn merge --ignore-ancestry -c 1600994 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1600995 13f79535-47bb-0310-9956-ffa450edef68