anchor.diff:    DataReference get selected => props['selected'];
     DataReference get loading => props['loading'];
     DataReference get active => props['active'];
  +  bool get fixedWidth => props['fixedWidth'];
   
     List get items => props['items'];
     String get selectorText => props['selectorText'];
  
positive.code:     var textSpan = span({'key': selectorText,
        'className' : 'round-selector-text'}, selectorText);
      var leftArrowDiv = div({'key': 'leftArrow',
        'className' : 'left-arrow'}, leftArrowButton);
      var selectorItemsListDiv = div({'ref' : 'itemsDiv',
        'className' : 'round-list-fixed-width'},
          div({'ref' : 'round-list', 'className' : 'round-list'}, _items));
      var rightArrowDiv = div({'key': 'rightArrow',
        'className' : 'right-arrow'}, rightArrowButton);
  
      List children = [textSpan, leftArrowDiv, selectorItemsListDiv, rightArrowDiv];
      if (_showFirstLast) {
  
negative.code: 
    get _visibleItemsWindowSize => ref('itemsDiv') != null ? ref('itemsDiv').marginEdge.width : null;
    get _spanWidth => ref('${items[0][VALUE]}') != null ? ref('${items[0][VALUE]}').marginEdge.width : null;
  
    get shouldDrawRight => ref('round-list').style.marginLeft > getMinMarginLeft();
    get shouldDrawLeft => ref('round-list').style.marginLeft < 0;
  
    var browserWindow;
  
  