Python test fixes, and removal of WrapDynamic.

Author: rxin

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/dsl/package.scala

@@ -272,9 +272,6 @@ package object dsl {
     def sfilter[T1](arg1: Symbol)(udf: (T1) => Boolean) =
       Filter(ScalaUdf(udf, BooleanType, Seq(UnresolvedAttribute(arg1.name))), logicalPlan)
 
-    def sfilter(dynamicUdf: (DynamicRow) => Boolean) =
-      Filter(ScalaUdf(dynamicUdf, BooleanType, Seq(WrapDynamic(logicalPlan.output))), logicalPlan)
-
     def sample(
         fraction: Double,
         withReplacement: Boolean = true,

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/WrapDynamic.scala

@@ -116,9 +116,9 @@ object EvaluatePython {
   def toJava(obj: Any, dataType: DataType): Any = (obj, dataType) match {
     case (null, _) => null
 
-    case (row: Seq[Any], struct: StructType) =>
+    case (row: Row, struct: StructType) =>
       val fields = struct.fields.map(field => field.dataType)
-      row.zip(fields).map {
+      row.toSeq.zip(fields).map {
         case (obj, dataType) => toJava(obj, dataType)
       }.toArray
 

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

@@ -458,21 +458,11 @@ private[sql] object JsonRDD extends Logging {
         gen.writeEndArray()
 
       case (MapType(kv,vv, _), v: Map[_,_]) =>
-        gen.writeStartObject
+        gen.writeStartObject()
         v.foreach { p =>
           gen.writeFieldName(p._1.toString)
           valWriter(vv,p._2)
         }
-        gen.writeEndObject
-
-      case (StructType(ty), v: Seq[_]) =>
-        gen.writeStartObject()
-        ty.zip(v).foreach {
-          case (_, null) =>
-          case (field, v) =>
-            gen.writeFieldName(field.name)
-            valWriter(field.dataType, v)
-        }
         gen.writeEndObject()
 
       case (StructType(ty), v: Row) =>