anchor.diff:        // FIXME: Strange to have the toolbar be tapable.
         center: new Listener(
           onPointerDown: handleToolbarPointerDown,
  -        child: new Text(toolbarCaption, style: Theme.of(this).text.title)
  +        child: new Text(toolbarCaption, style: Theme.of(context).text.title)
         )
       );
     }
   
  -  Widget build() {
  +  Widget build(BuildContext context) {
       // We build the board before we build the toolbar because we compute the win state during build step.
       Widget board = buildBoard();
       return new Title(
         title: 'Mine Digger',
         child: new Scaffold(
  -        toolbar: buildToolBar(),
  +        toolbar: buildToolBar(context),
           body: new Container(
             child: new Center(child: board),
             decoration: new BoxDecoration(backgroundColor: Colors.grey[50])
  
positive.code:   final int posX;
    final int posY;
  
    Widget build() {
      Widget text;
      if (flagged)
        text = buildInnerCell(new StyledText(elements : [textStyles[5], '\u2691']));
  
negative.code:   }
  }
  
  class ExposedMineNode extends StatelessComponent {
  
    ExposedMineNode({ this.state, this.count });
  
    final CellState state;
    final int count;
  
    Widget build(BuildContext context) {
      StyledText text;
      if (state == CellState.cleared) {
        // Uncovered cell with nearby mine count.
  