anchor.diff:        if (_markerSubscription == null) {
           _markerSubscription = file.workspace.onMarkerChange.listen(
               _handleMarkerChange);
  +        currentSession.onChange.listen(
  +            (_) => setMarkers(currentFile.getMarkers()));
         }
       }
     }
  
positive.code:           type: annotationType);
        annotations.add(annotation);
  
        // TODO(ericarnold): This won't work with code folding.  Fix
        double markerHeightPercentage =
            marker.lineNum / numberLines * 100;
  
        html.Element minimapMarker = new html.Element.div();
        minimapMarker.classes.add("minimap-marker error");
  
negative.code: class AceEditor extends Editor {
    final AceContainer aceContainer;
  
    workspace.File _file;
  
    workspace.File get file => _file;
  
    set file (workspace.File file) {
      this._file = file;
  //    aceContainer.setMarkers(file.getMarkers());
    }
  
    html.Element get element => aceContainer.parentElement;
  
    AceEditor(this.aceContainer) {
    }
  
    void resize() => aceContainer.resize();
  
  