private Gmail getOrCreateGmail(TokensAndUrlAuthData authData) {
    return gmail == null ? makeGmailService(authData) : gmail;
  }
Creates the given {@code labelName} in the import service provider and returns the id.
extensions/data-transfer/portability-data-transfer-google/src/main/java/org/datatransferproject/datatransfer/google/mail/GoogleMailImporter.java