anchor.diff:    }
   
     Future connect() {
  +    //on connect request quota from browser
  +    window.navigator.persistentStorage.requestQuota(size);
       return new Completer()..complete().future;
     }
   
  
positive.code: class FileSystemAccess extends Protocol {
    Future<List<File>> list(String path) {
      var completer = new Completer();
      window.navigator.persistentStorage.requestQuota(size);
      window.requestFileSystem(size, persistent: persistent).then((fs){
        List<File> files = new List<File>();
        DirectoryEntry root = fs.root;
  
negative.code:   }
  
    Stream<List<int>> open(String path) {
      FileSystem fileSystem;
      window.requestFileSystem(size, persistent: persistent).then((fs){
        fileSystem = fs;
      });
      while(fileSystem == null) {
      }
      return fs.root.getFile(path).asStream();
    }
  
    StreamConsumer openWrite(String path) {
  