apache/spark — pull request #1705 by yhuai (2014-08-01 00:25:40+00:00)
Title: [SPARK-2779] [SQL] asInstanceOf[Map[...]] should use scala.collection.Map instead of scala.collection.immutable.Map

Since we let users create Rows. It makes sense to accept mutable Maps as values of MapType columns.

JIRA: https://issues.apache.org/jira/browse/SPARK-2779