Fix deadlock in HdfsScanNode.

Change-Id: I74a38f30c7793c4ace9d2446850a42e821f68bf2
Reviewed-on: http://gerrit.ent.cloudera.com:8080/2582
Reviewed-by: Henry Robinson <henry@cloudera.com>
Tested-by: jenkins
IMPALA-962: Fully qualify table and view names in toSql().

Change-Id: I6bf757c4ffbaf82c136af7b59d2d415234545a86
Reviewed-on: http://gerrit.ent.cloudera.com:8080/2373
Reviewed-by: Alex Behm <alex.behm@cloudera.com>
Tested-by: jenkins