anchor.diff:  class Outline {
     html.DivElement _outlineDiv;
     html.UListElement _rootList;
  +  html.DivElement _outlineContainer;
  +
     services.AnalyzerService analyzer;
   
     List<OutlineTopLevelItem> children = [];
  
positive.code: 
      _outlineDiv.style
          ..position = 'absolute'
          ..width = '200px'
          ..right = '10px'
          ..top ='10px'
          ..bottom = '10px'
          ..background = 'rgb(100, 100, 100)'
          ..borderRadius = '2px'
          ..zIndex = '100'
          ..opacity = '0.6';
    }
  
    /**
  
negative.code:   }
  
    /**
     * Toggles visibility of the outline.  Returns true if showing.
     */
    bool _toggle() {
      if (_outlineContainer.style.display == 'none') {
        _outlineContainer.style.display = 'block';
        return true;
      } else {
        _outlineContainer.style.display = 'none';
        return false;
      }
    }
  
  