anchor.diff:      // receiver explicitly and we need to pass it to the getter call.
       bool isInterceptedMethod = _interceptorData.isInterceptedMethod(member);
       bool isInterceptedClass =
  -        _interceptorData.isInterceptedClass(member.enclosingClass);
  +        _interceptorData.isInterceptedClass(member.enclosingClass!);
   
       const String receiverArgumentName = r'$receiver';
   
  
positive.code: 
  import '../common/elements.dart' show CommonElements;
  import '../common/names.dart' show Identifiers, Selectors;
  import '../constants/values.dart';
  import '../elements/entities.dart';
  import '../js/js.dart' as jsAst;
  import '../js/js.dart' show js;
  import '../js_backend/field_analysis.dart';
  import '../js_backend/namer_interfaces.dart' show Namer;
  import '../js_backend/interceptor_data.dart' show InterceptorData;
  import '../js_model/js_world.dart' show JClosedWorld;
  import '../options.dart';
  import '../universe/codegen_world_builder.dart';
  
negative.code:           continue;
          }
  
          SelectorConstraints maskSet = selectors[selector]!;
          if (maskSet.needsNoSuchMethodHandling(selector, _closedWorld)) {
            jsAst.Name jsName = _namer.invocationMirrorInternalName(selector);
            jsNames[jsName] = selector;
  