anchor.diff:      return ctrl.stream;
     }
   
  +  /// Triggered when layers in the [FeatureGroup] have been edited and saved.
     Stream<LayerGroup> get onDrawEdited {
       const type = 'draw:edited';
       JsObject map = control['_map'];
  
positive.code:     control.callMethod('setDrawingOptions', [_draw]);
    }
  
    Stream<Layer> get onDrawCreated {
      const type = 'draw:created';
      JsObject map = control['_map'];
  
negative.code: library leaflet.draw;
  
  import 'dart:async';
  import 'dart:js';
  import 'package:leaflet/leaflet.dart';
  