Merge r1578618 from branch-2. Fixed AM container log to show on NM web page after application finishes if log-aggregation is disabled. Contributed by Rohith Sharmaks

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.4@1578619 13f79535-47bb-0310-9956-ffa450edef68