This test has a number of issues:
- it side steps the normal job submission API for no apparent reason, manually writing splits file and uploading submission files. (but forgets to upload the job jar, so the jobs all fail)
- it doesn't call waitForCompletion, or check job status (so it doesn't notice that the jobs all fail)
- it doesn't verify in any way that the job output is owned by the user who supposedly ran the job
- it shuts down DFS before MR
These all conspire to make it pass, but it isn't actually testing anything.