spark git commit: [SPARK-15441][SQL] support null object in Dataset outer-join

Repository: spark Updated Branches: refs/heads/branch-2.0 8cdc0d4da -> 91812226f [SPARK-15441][SQL] support null object in Dataset outer-join ## What changes were proposed in this pull request? Currently we can't encode top level null object into internal row, as Spark SQL doesn't allow row

spark git commit: [SPARK-15441][SQL] support null object in Dataset outer-join

Repository: spark Updated Branches: refs/heads/master 7bb64aae2 -> 8640cdb83 [SPARK-15441][SQL] support null object in Dataset outer-join ## What changes were proposed in this pull request? Currently we can't encode top level null object into internal row, as Spark SQL doesn't allow row to b