anchor.diff:          .catchError((e) => _systemModalComplete());
     }
   
  -  Future importFolder([List<ws.Resource> resources,
  -                       chrome.DirectoryEntry entry]) {
  +  Future<SparkJobStatus> importFolder([List<ws.Resource> resources,
  +                                      chrome.DirectoryEntry entry]) {
       return _beforeSystemModal()
           .then((_) => super.importFolder(resources, entry))
           .whenComplete(() => _systemModalComplete());
  
positive.code: import 'lib/jobs.dart';
  import 'lib/platform_info.dart';
  import 'lib/preferences.dart';
  import 'lib/workspace.dart' as ws;
  
  class _TimeLogger {
  
negative.code: class SparkPolymer extends Spark {
    SparkPolymerUI _ui;
  
    Future<SparkJobStatus> openFolder(chrome.DirectoryEntry entry) {
      return _beforeSystemModal()
          .then((_) => super.openFolder(entry))
          .then((status) {
            _systemModalComplete();
            return status;
          }).catchError((e) => _systemModalComplete());
    }
  
    Future openFile() {
  