Make hasNext a getter instead of a method.

lib/compiler/implementation/resolution/members.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.
 
 abstract class TreeElements {
   Element operator[](Node node);
   Selector getSelector(Send send);
   DartType getType(TypeAnnotation annotation);
   bool isParameterChecked(Element element);
 }
@@ skipping 2060 matching lines @@
       mapping[node.target] = label;
     }
     mapping[node] = target;
   }
 
   registerImplicitInvocation(SourceString name, int arity) {
     Selector selector = new Selector.call(name, null, arity);
     world.registerDynamicInvocation(name, selector);
   }
 
+  registerImplicitFieldGet(SourceString name) {
+    Selector selector = new Selector.getter(name, null);
+    world.registerDynamicGetter(name, selector);
+  }
+
   visitForIn(ForIn node) {
     for (final name in const [
         const SourceString('iterator'),
-        const SourceString('next'),
-        const SourceString('hasNext')]) {
+        const SourceString('next')]) {
       registerImplicitInvocation(name, 0);
     }
+    registerImplicitFieldGet(const SourceString('hasNext'));
     visit(node.expression);
     Scope blockScope = new BlockScope(scope);
     Node declaration = node.declaredIdentifier;
     visitIn(declaration, blockScope);
     visitLoopBodyIn(node, node.body, blockScope);
 
     // TODO(lrn): Also allow a single identifier.
     if ((declaration is !Send || declaration.asSend().selector is !Identifier
         || declaration.asSend().receiver != null)
         && (declaration is !VariableDefinitions ||
@@ skipping 1093 matching lines @@
     return result;
   }
   Element lookup(SourceString name) => localLookup(name);
   Element lexicalLookup(SourceString name) => localLookup(name);
 
   Element add(Element newElement) {
     throw "Cannot add an element in a patch library scope";
   }
   String toString() => 'PatchLibraryScope($origin,$patch)';
 }