anchor.diff:  
     /// The set of names that are `noSuchMethod` forwarders in [implemented].
     final Set<Name> _noSuchMethodForwarders;
  -
  -  /// The map of names to their concrete implementations that can be mixed
  -  /// when this type is used as a mixin.
  -  final Map<Name, ExecutableElement> _implementedForMixing;
   
     /// The map of names to their signatures from the mixins, superclasses,
     /// or interfaces.
  
positive.code:       declared,
        implemented,
        noSuchMethodForwarders,
        implementedForMixing,
        namedCandidates,
        superImplemented,
        conflicts ?? const [],
  
negative.code:     this.declared,
      this.implemented,
      this._noSuchMethodForwarders,
      this._overridden,
      this._superImplemented,
      this.conflicts,
  