anchor.diff:    void initializeHolders() {
       void _addMembers(Holder holder, List<Method> methods) {
         for (var method in methods) {
  -        memberEntityMap[method.element] = holder;
  +        final element = method.element;
  +        if (element == null) continue;
  +        memberEntityMap[element] = holder;
           if (method is DartMethod) {
             _addMembers(holder, method.parameterStubs);
           }
  
positive.code: // Copyright (c) 2021, 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.
  
  // @dart = 2.10
  
  import 'package:js_ast/src/precedence.dart' as js show PRIMARY;
  import 'package:front_end/src/api_unstable/dart2js.dart' show $A;
  
negative.code:   final Holder globalObjectForInterceptors =
        Holder(globalObjectNameForInterceptors());
    final Set<Holder> allHolders = {};
    DeferredHolderResource? mainHolderResource;
    Holder? mainHolder;
    Holder? mainConstantHolder;
  
    /// Maps of various object types to the holders they ended up in.
    final Map<ClassEntity, Holder> classEntityMap = {};
  