anchor.diff:            (ClassEntity cls, MemberEntity member) {
           // All methods on [Object] are shadowed by [Interceptor].
           if (cls == _commonElements.objectClass) return;
  -        Set<MemberEntity> set = _interceptedElements[member.name] ??= {};
  +        final set = _interceptedElements[member.name!] ??= {};
           set.add(member);
         });
       }
  
positive.code:       if (member.name == Identifiers.call) return;
        // All methods on [Object] are shadowed by [Interceptor].
        if (cls == _commonElements.objectClass) return;
        Set<MemberEntity> set = _interceptedElements[member.name] ??= {};
        set.add(member);
      });
  
  
negative.code:   @override
    Set<ClassEntity> getInterceptedClassesOn(
        String name, JClosedWorld closedWorld) {
      final intercepted = interceptedMembers[name];
      if (intercepted == null) return _noClasses;
      return _interceptedClassesCache.putIfAbsent(name, () {
        // Populate the cache by running through all the elements and
        // determine if the given selector applies to them.
        Set<ClassEntity> result = {};
        for (MemberEntity element in intercepted) {
          final classElement = element.enclosingClass!;
          if (_isCompileTimeOnlyClass(classElement)) continue;
          if (_nativeData.isNativeOrExtendsNative(classElement) ||
              interceptedClasses.contains(classElement)) {
            result.add(classElement);
          }
          if (classesMixedIntoInterceptedClasses.contains(classElement)) {
            final nativeSubclasses =
                nativeSubclassesOfMixin(classElement, closedWorld);
            if (nativeSubclasses != null) result.addAll(nativeSubclasses);
          }
  