anchor.diff:    ///
     /// It's possible the element will end up not being an [ElementAst].
     StandaloneTemplateAst parseElement(
  -      NgToken beginToken, Queue<String> tagStack) {
  +      NgToken beginToken, List<String> tagStack) {
       var isTemplateElement = false;
   
       // Parse the element identifier.
  
positive.code: // Copyright (c) 2016, 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 'dart:collection';
  
  import 'package:source_span/source_span.dart';
  import 'package:string_scanner/string_scanner.dart';
  
negative.code:           childNodes.add(childAst);
          }
        }
        tagStack.removeLast();
      }
  
      if (isTemplateElement) {
  