HIVE-5071 : Address thread safety issues with HiveHistoryUtil (Teddy Choi reviewed by Edward Capriolo committed by Navis)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1520979 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk-gd