@RequiresEdt
  public boolean tryRegisterDownloadingListener(@NotNull Sdk sdk,
                                                @NotNull Disposable lifetime,
                                                @Nullable ProgressIndicator indicator,
                                                @NotNull Consumer<? super Boolean> onDownloadCompleteCallback) {
    PendingDownload pd = findTask(sdk);
    if (pd == null) return false;

    pd.registerListener(lifetime, indicator, onDownloadCompleteCallback);
    return true;
  }
@RequiresEdt
  public boolean tryRegisterDownloadingListener(@NotNull Sdk sdk,
                                                @NotNull Disposable lifetime,
                                                @Nullable ProgressIndicator indicator,
                                                @NotNull Consumer<? super Boolean> onDownloadCompleteCallback)