anchor.diff:    ColorValue colorBoxValue = new ColorValue();
     ColorValue colorValue = new ColorValue();
     
  +  ColorData externalStop;
  +  
     bool _down = false;
     BaseSlider target;
     
  
positive.code:   // Called by either an external control (aka gradient_colorstops_control)
    void externalColorChange(ColorData stop) {
      _transmit = false;
      
      // An external control is telling us to switch to a new color configuration.
      color = stop.color;
  
negative.code:       stop.color = color;
        stop.whiteness = bright;
        stop.darkness = dark;
        stop.gradientlocation = externalStop.gradientlocation;
        _colorChangeCallback(stop);
      }
    }
  