Generate prettier loops.

frog/leg/resolver.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.
 
 interface TreeElements {
   Element operator[](Node node);
   Selector getSelector(Send send);
 }
 
 class TreeElementMapping implements TreeElements {
@@ skipping 1060 matching lines @@
       LabelElement label = statementScope.lookupLabel(labelName);
       if (label === null) {
         error(node.target, MessageKind.UNBOUND_LABEL, [labelName]);
         return;
       }
       target = label.target;
       if (!target.statement.isValidContinueTarget()) {
         error(node.target, MessageKind.INVALID_CONTINUE, [labelName]);
       }
       label.setContinueTarget();
+      mapping[node.target] = label;
     }
     mapping[node] = target;
   }
 
-  visitForInStatement(ForInStatement node) {
+  visitForIn(ForIn node) {
     visit(node.expression);
     Scope scope = new BlockScope(context);
     Node declaration = node.declaredIdentifier;
     visitIn(declaration, scope);
     visitLoopBodyIn(node, node.body, scope);
 
     // TODO(lrn): Also allow a single identifier.
     if ((declaration is !Send || declaration.asSend().selector is !Identifier)
         && (declaration is !VariableDefinitions ||
         !declaration.asVariableDefinitions().definitions.nodes.tail.isEmpty()))
@@ skipping 695 matching lines @@
 
   TopScope(LibraryElement library) : super(null, library);
   Element lookup(SourceString name) {
     return library.find(name);
   }
 
   Element add(Element element) {
     throw "Cannot add an element in the top scope";
   }
 }