anchor.diff:     */
     static Future<ProjectLocationManager> restoreManager(Spark spark,
         String folderToken) {
  +
  +    // If there is nothing to restore, create a new ProjectLocationManager.
       if (folderToken == null) {
         return new Future.value(new ProjectLocationManager._(spark));
       }
  
positive.code:     return new Future.value(entry.fullPath);
    }
  
    Future restoreManager(Spark spark, String folderToken) =>
        throw "Can't restore mock manager";
  
    Future<ProjectLocationManager> restoreMockManager(Spark spark) {
      return MockProjectLocationManager.restoreManager(spark)
          .then((ProjectLocationManager manager) {
            _locationManager = manager;
  
negative.code: }
  
  Future<ProjectLocationManager> restoreManager(Spark spark) {
    return spark.localPrefs.getValue('projectFolder').then((String folderToken) {
      return fileSystemAccess.restoreManager(spark, folderToken);
    });
  }
  
  /**
   * Provides abstracted access to all filesystem functions
   */
  class FileSystemAccess {
    ProjectLocationManager _locationManager;
  