private void performRefresh() {
    Set<String> toRefresh;
    synchronized (myLock) {
      toRefresh = myRefreshQueue;
      myRefreshQueue = new HashSet<>();
      myScheduledFuture = null;
    }
    List<VirtualFile> files = ContainerUtil.mapNotNull(toRefresh, mySystem::findFileByPath);
    RefreshQueue.getInstance().refresh(false, false, null, files);
  }
private void performRefresh()