attempt at making menuitems react

sky/examples/fn/widgets/checkbox.dart

 part of widgets;
 
 class Checkbox extends ButtonBase {
 
   bool checked;
   ValueChanged onChanged;
 
   static Style _style = new Style('''
+    transform: translateX(0);
     display: flex;
     justify-content: center;
     align-items: center;
     -webkit-user-select: none;
     cursor: pointer;
     width: 30px;
     height: 30px;'''
   );
 
   static Style _containerStyle = new Style('''
@@ skipping 35 matching lines @@
   Checkbox({ Object key, this.onChanged, this.checked }) : super(key: key);
 
   Node render() {
     return new Container(
       style: _style,
       onClick: _handleClick,
       onPointerDown: _handlePointerDown,
       onPointerUp: _handlePointerUp,
       onPointerCancel: _handlePointerCancel,
       children: [
+        super.render(),
         new Container(
           style: _highlight ? _containerHighlightStyle : _containerStyle,
           children: [
             new Container(
               style: checked ? _checkedStyle : _uncheckedStyle
             )
           ]
         )
       ]
     );
   }
 
   void _handleClick(sky.Event e) {
     onChanged(!checked);
   }
 }