apache/spark — pull request #2325 by liancheng (2014-09-09 00:50:33+00:00)
Title: [SPARK-3448][SQL] Check for null in SpecificMutableRow.update

`SpecificMutableRow.update` doesn't check for null, and breaks existing `MutableRow` contract.

The tricky part here is that for performance considerations, the `update` method of all subclasses of `MutableValue` doesn't check for null and sets the null bit to false.