anchor.diff:        cells.where((ColorPaletteCellElement e) => e.selected)
           .toList(growable: false);
   
  -  ColorPaletteElement.created() : super.created() {
  +  ColorPaletteElement.created() : super.created();
  +
  +  @override
  +  ready() {
       _initEvents();
     }
   
  
positive.code:       cells.firstWhere((ColorPaletteCellElement e) => e.selected,
          orElse: () => null);
  
    @reflectable
    String get color {
      final c = selectedCell;
  
negative.code:   detached() {
      super.detached();
      _cellObserver.disconnect();
    }
  
    void select(ColorPaletteCellElement cell) {
      if (!contains(cell)) throw new ArgumentError('Expected to be a descendant cell');
      cell.select();
    }
  
    void _startCellObserver() {
  