Introduce .isMalformed

pkg/compiler/lib/src/resolution/tree_elements.dart

 // Copyright (c) 2015, 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.
 
 library dart2js.resolution.tree_elements;
 
 import '../common.dart';
 import '../constants/expressions.dart';
 import '../dart_types.dart';
 import '../elements/elements.dart';
@@ skipping 131 matching lines @@
 
   final int hashCode = ++_hashCodeCounter;
   static int _hashCodeCounter = 0;
 
   TreeElementMapping(this.analyzedElement);
 
   operator []=(Node node, Element element) {
     // TODO(johnniwinther): Simplify this invariant to use only declarations in
     // [TreeElements].
     assert(invariant(node, () {
-      if (!element.isErroneous && analyzedElement != null && element.isPatch) {
+      if (!element.isMalformed && analyzedElement != null && element.isPatch) {
         return analyzedElement.implementationLibrary.isPatch;
       }
       return true;
     }));
     // TODO(ahe): Investigate why the invariant below doesn't hold.
     // assert(invariant(node,
     //                  getTreeElement(node) == element ||
     //                  getTreeElement(node) == null,
     //                  message: '${getTreeElement(node)}; $element'));
 
@@ skipping 339 matching lines @@
   }
 
   void setCurrentTypeMask(ForIn node, TypeMask mask) {
     _setTypeMask(node.inToken, mask);
   }
 
   TypeMask getCurrentTypeMask(ForIn node) {
     return _getTypeMask(node.inToken);
   }
 }