Update NumColumns counter correctly in the parquet scanner
Update NumColumns counter correctly in the parquet scanner

Without this patch, NumColumns is always 0

Change-Id: I09b29c97f87e7ad65a50ddebc9d5907e7955b879
Reviewed-on: http://gerrit.cloudera.org:8080/57
Reviewed-by: Matthew Jacobs <df2fa7c39d141dc5dc5589fed74180e757ed6c9a@cloudera.com>
Tested-by: Internal Jenkins

michaelhkw/incubator-impala,michaelhkw/incubator-impala,cloudera/Impala,cloudera/Impala,michaelhkw/incubator-impala,michaelhkw/incubator-impala,cloudera/Impala,michaelhkw/incubator-impala,cloudera/Impala,cloudera/Impala,michaelhkw/incubator-impala,michaelhkw/incubator-impala,cloudera/Impala,cloudera/Impala