SPARK-1770: Revert accidental(?) fix

Looks like this change was accidentally committed here: https://github.com/apache/spark/commit/06b15baab25951d124bbe6b64906f4139e037deb
but the change does not show up in the PR itself (#704).

Other than not intending to go in with that PR, this also broke the test JavaAPISuite.repartition.

Author: Aaron Davidson <aaron@databricks.com>

Closes #716 from aarondav/shufflerand and squashes the following commits:

b1cf70b [Aaron Davidson] SPARK-1770: Revert accidental(?) fix