If a intermediate file size less than the chunk size, it does not close.
Created a review request against branch master in reviewboard
This issue got +1 from reviewboard.
I've just committed it to master branch.
FAILURE: Integrated in Tajo-master-build #7 (See https://builds.apache.org/job/Tajo-master-build/7/)
TAJO-488: Data fetcher doesn't close small file in shuffle. (jinho) (jinossy: https://git-wip-us.apache.org/repos/asf?p=incubator-tajo.git&a=commit&h=c4b81569ad2a1ee5fa1695016a7aded6c9f7e512)