HIVE-8934: Investigate test failure on bucketmapjoin10.q and bucketmapjoin11.q [Spark Branch] (Chao via Xuefu)

git-svn-id: https://svn.apache.org/repos/asf/hive/branches/spark@1642018 13f79535-47bb-0310-9956-ffa450edef68