Mark SQLContext transient and put it in a second param list.

The second part follows the current pattern of the rest of Spark SQL codebase.

Author: concretevitamin

sql/core/src/main/scala/org/apache/spark/sql/execution/SparkStrategies.scala

@@ -221,7 +221,7 @@ private[sql] abstract class SparkStrategies extends QueryPlanner[SparkPlan] {
   case class SetCommandStrategy(context: SQLContext) extends Strategy {
     def apply(plan: LogicalPlan): Seq[SparkPlan] = plan match {
       case logical.SetCommand(key, value) =>
-        Seq(execution.SetCommandPhysical(key, value, context))
+        Seq(execution.SetCommandPhysical(key, value)(context))
       case _ => Nil
     }
   }

sql/core/src/main/scala/org/apache/spark/sql/execution/commands.scala

@@ -26,12 +26,8 @@ import org.apache.spark.sql.catalyst.expressions.{GenericRow, Attribute}
  * :: DeveloperApi ::
  */
 @DeveloperApi
-case class SetCommandPhysical(
-    key: Option[String],
-    value: Option[String],
-    context: SQLContext)
-  extends LeafNode {
-
+case class SetCommandPhysical(key: Option[String], value: Option[String])
+                             (@transient context: SQLContext) extends LeafNode {
    def execute(): RDD[Row] = (key, value) match {
      case (Some(k), Some(v)) => context.emptyResult
      case (Some(k), None) =>