anchor.diff:  
     /// Mirror to [PhotoView.tightMode]
     final bool tightMode;
  +
  +  /// Mirror to [PhotoView.disableGestures]
  +  final bool disableGestures;
   
     /// Quality levels for image filters.
     final FilterQuality filterQuality;
  
positive.code:     this.gestureDetectorBehavior,
      this.tightMode,
      this.filterQuality,
    })  : child = null,
          childSize = null,
          assert(imageProvider != null);
  
    PhotoViewGalleryPageOptions.customChild({
      @required this.child,
      this.childSize,
      this.heroAttributes,
  
negative.code:             tightMode: pageOption.tightMode,
              filterQuality: pageOption.filterQuality,
              basePosition: pageOption.basePosition,
              disableGestures: pageOption.disableGestures,
            );
  
      return ClipRect(
  