DownloadManager lanza SecurityException en Android Q

Download Manager obtiene el siguiente error en dispositivos con Android 10. La versión de destino es 29.

Agregué una android:requestLegacyExternalStorage="true"etiqueta al manifiesto, pero no funcionó.

java.lang.SecurityException: ruta / almacenamiento / emulado / 0 / Contenido / Awesome App.apk no admitidos

Aqui esta el codigo

public static void startDownload(Context context, String url, String token, String subPath) {

    DownloadManager.Request request;
    DownloadManager manager = (DownloadManager) context.getSystemService(Context.DOWNLOAD_SERVICE);
    Uri uri = Uri.parse(url);  // A url to download a file

    try {
        request = new DownloadManager.Request(uri);
        request.addRequestHeader("X-Auth-Token", token);
    } catch (IllegalArgumentException e) {
        e.printStackTrace();
        return;
    }

    request.setVisibleInDownloadsUi(true);
    request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE);

    try {
        File downloadFileDir = new File(Environment
                .getExternalStorageDirectory().getAbsolutePath() + "/Contents");

        if (downloadFileDir != null) {
            if (!downloadFileDir.exists()) {
                downloadFileDir.mkdirs();
            }

            File file = new File(downloadFileDir.getAbsolutePath() + File.separator + subPath);
            // subPath is name of the file to download. e.g. Awesome App.apk
            if (file.exists()) {
                file.delete();
            }

            Uri localUri = Uri.fromFile(file);
            request.setDestinationUri(localUri);
            if (localUri != null) {
                request.setMimeType(MimeTypeMap.getSingleton().getMimeTypeFromExtension(MimeTypeMap.getFileExtensionFromUrl(localUri.toString())));
            }
        }
    } catch (SecurityException e) {
        e.printStackTrace();
    }

    request.setTitle(subPath);
    request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);

    try {
        manager.enqueue(request);
    } catch (SecurityException e) {
        e.printStackTrace();
        //Got exception here
    }
}