anchor.diff:          field.isFinal ? 'finalFieldType(#)' : 'fieldType(#)', [args]);
     }
   
  -  DartType _getMemberRuntimeType(Member member, Class fromClass) {
  +  DartType _memberRuntimeType(Member member, Class fromClass) {
       var f = member.function;
       if (f == null) {
         return (member as Field).type;
  
positive.code:     if (target is Field || target is Procedure && target.isAccessor) {
        var fromType = target.getterType;
        if (fromType is InterfaceType) {
          var callName = _getImplicitCallTarget(fromType);
          if (callName != null) {
            return js.call('#.#.#(#)', [jsReceiver, jsName, callName, args]);
          }
  
negative.code:         gen = js.call('() => #(#)', [gen, mutatedParams]);
        }
  
        var returnType = _expectedReturnType(function, _coreTypes.iterableClass);
        var syncIterable =
            _emitType(InterfaceType(_syncIterableClass, [returnType]));
        return js.call('new #.new(#)', [syncIterable, gen]);
  