Update elements, nodes and visitors for serialization.

pkg/compiler/lib/src/tree/prettyprint.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import '../tokens/token.dart' show BeginGroupToken, Token;
 import '../util/util.dart';
 import 'nodes.dart';
 
 /**
  * Pretty-prints Node tree in XML-like format.
@@ skipping 106 matching lines @@
   }
 
   visitExpressionStatement(ExpressionStatement node) {
     visitNodeWithChildren(node, "ExpressionStatement");
   }
 
   visitFor(For node) {
     visitNodeWithChildren(node, "For");
   }
 
+  visitForIn(ForIn node) {
+    node.visitChildren(this);
+    closeNode();
+  }
+
   visitAsyncForIn(AsyncForIn node) {
     openNode(node, "AsyncForIn");
+    visitForIn(node);
   }
 
   visitSyncForIn(SyncForIn node) {
-    openNode(node, "ForIn");
-    node.visitChildren(this);
-    closeNode();
+    openNode(node, "SyncForIn");
+    visitForIn(node);
   }
 
   visitFunctionDeclaration(FunctionDeclaration node) {
     visitNodeWithChildren(node, "FunctionDeclaration");
   }
 
   visitFunctionExpression(FunctionExpression node) {
     openNode(node, "FunctionExpression", {
       "getOrSet" : tokenToStringOrNull(node.getOrSet)
     });
@@ skipping 327 matching lines @@
   }
 
   visitGotoStatement(GotoStatement node) {
     unimplemented('visitNode', node: node);
   }
 
   unimplemented(String message, {Node node}) {
     throw message;
   }
 }