anchor.diff:  
   final Logger _logger = new Logger('atom.tooltip');
   
  -/// Controls the hover tooltip with type information feature, capable of installing the feature
  -/// into every active .dart editor.
  +/// Controls the hover tooltip with type information feature, capable of
  +/// installing the feature into every active .dart editor.
   class TooltipController implements Disposable {
     Disposables _disposables = new Disposables();
   
  
positive.code:     });
    }
  
    void dispose() {
      _disposables.dispose();
    }
  
    /// Installs the feature into [editor] if it responsible for a .dart file, noop if not.
    void _installInto(TextEditor editor) {
      if (!isDartFile(editor.getPath())) return;
  
      new TooltipManager(editor);
    }
  }
  
  /// Manages the display of tooltips for a single [TextEditor].
  
negative.code:   String _tooltipContent(HoverInformation hover) =>
        hover.elementDescription ?? hover.staticType ?? hover.propagatedType;
  
    void _disposeTooltip() => _tooltipElement?.dispose();
  
    void dispose() => _disposeTooltip();
  }
  
  /// Basic tooltip element with single [String] content capable of attaching
  /// itself to a [TextEditor] at a given position relative to its top,left corner.
  class TooltipElement extends CoreElement {
    static const int _offset = 12;
  
  