HIVE-7904: Missing null check cause NPE when updating join column stats in statistics annotation (Prasanth J reviewed by Gunther Hagleitner)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1621250 13f79535-47bb-0310-9956-ffa450edef68
HIVE-7557 : When reduce is vectorized, dynpart_sort_opt_vectorization.q under Tez fails (Matt McCline, reviwed by Jitendra)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1621262 13f79535-47bb-0310-9956-ffa450edef68