anchor.diff:      }).catchError((e) => null);
     }
   
  -  void openProject() {
  +  void openFolder() {
       chrome.ChooseEntryOptions options = new chrome.ChooseEntryOptions(
           type: chrome.ChooseEntryType.OPEN_DIRECTORY);
       chrome.fileSystem.chooseEntry(options).then((chrome.ChooseEntryResult result) {
  
positive.code:   }
  }
  
  class ProjectOpenAction extends SparkAction {
    ProjectOpenAction(Spark spark) : super(spark, "project-open", "Open Project...");
  
    void _invoke([Object context]) => spark.openProject();
  }
  
  class AboutSparkAction extends SparkAction {
  
negative.code: 
      ul.children.add(createMenuItem(actionManager.getAction('file-new')));
      ul.children.add(createMenuItem(actionManager.getAction('file-open')));
      ul.children.add(createMenuItem(actionManager.getAction('folder-open')));
      ul.children.add(createMenuItem(actionManager.getAction('file-delete')));
      ul.children.add(createMenuItem(actionManager.getAction('file-close')));
      ul.children.add(createMenuSeparator());
  