anchor.diff:    TrimPath get trim => _trim;
     bool get isTrimmed => _trim != TrimPath.Off;
   
  -  double _trimStart;
  +  double _trimStart = 0.0;
     double get trimStart => _trimStart;
     set trimStart(double value) {
       if (_trimStart == value) {
  
positive.code:     markPathEffectsDirty();
    }
  
    double _trimEnd;
    double get trimEnd => _trimEnd;
    set trimEnd(double value) {
      if (_trimEnd == value) {
  
negative.code:     markPathEffectsDirty();
    }
  
    double _trimOffset = 0.0;
    double get trimOffset => _trimOffset;
    set trimOffset(double value) {
      if (_trimOffset == value) {
  