anchor.diff:  import 'package:analyzer/dart/element/type.dart';
   import 'package:analyzer/error/error.dart';
   import 'package:analyzer/src/dart/analysis/testing_data.dart';
  +import 'package:analyzer/src/dart/element/inheritance_manager3.dart';
   import 'package:analyzer/src/util/ast_data_extractor.dart';
   
   import '../util/id_testing_helper.dart';
  
positive.code: }
  
  class _InheritanceDataExtractor extends AstDataExtractor<String> {
    _InheritanceDataExtractor(Uri uri, Map<Id, ActualData<String>> actualMap)
        : super(uri, actualMap);
  
  
negative.code:   void computeForClass(Declaration node, Id id) {
      super.computeForClass(node, id);
      if (node is ClassDeclaration) {
        var element = node.declaredElement;
  
        void registerMember(
            MemberId id, int offset, Object object, DartType type) {
  