HIVE-4665 : error at VectorExecMapper.close in group-by-agg query over ORC, vectorized (Jitendra Nath Pandey via Ashutosh Chauhan)

git-svn-id: https://svn.apache.org/repos/asf/hive/branches/vectorization@1490491 13f79535-47bb-0310-9956-ffa450edef68