anchor.diff:  
     void draw(ui.Canvas canvas) {
       for (ActorDrawable drawable in drawableNodes) {
  -      if (drawable is FlutterActorShape) {
  -        drawable.draw(canvas);
  +      if (drawable is FlutterActorDrawable) {
  +        (drawable as FlutterActorDrawable).draw(canvas);
         }
       }
     }
  
positive.code:     return _path;
    }
  }
  
negative.code: export 'package:flare_dart/actor_node.dart';
  import 'trim_path.dart';
  
  abstract class FlutterActorDrawable {
    void draw(ui.Canvas canvas);
  }
  
  abstract class FlutterFill {
    ui.Paint _paint;
    void initializeGraphics() {
  