HIVE-4935 : Potential NPE in MetadataOnlyOptimizer (Yin Huai via Ashutosh Chauhan)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1507342 13f79535-47bb-0310-9956-ffa450edef68
HIVE-4521 Auto join conversion fails in certain cases (Gunther Hagleitner via omalley)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1484623 13f79535-47bb-0310-9956-ffa450edef68