anchor.diff:        _currentState = state;
         _selectedController.add(currentFile);
         if (state == null) {
  -        _aceContainer.switchTo(null);
  +        _aceManager.switchTo(null);
           persistState();
         } else {
           // Clear text content of ACE editor.
  -        _aceContainer.switchTo(null);
  +        _aceManager.switchTo(null);
   
           if (!state.hasSession) {
             _newFileOpenedController.add(null);
  
positive.code:   final StreamController<File> _selectedController =
        new StreamController.broadcast();
  
    EditorManager(this._workspace, this._aceContainer, this._prefs,
        this._eventBus, this._services) {
  
      // TODO(ericarnold): This is temporary.  Everything should use
  
negative.code:     if (editorType(file.name) == EDITOR_TYPE_IMAGE) {
        editor = new ImageViewer(file);
      } else {
        editor = new ace.TextEditor(_aceManager, file, _prefs);
        editor.resize();
      }
  
  