hint phonenumber

// Construct a request for phone numbers and show the picker
private fun requestHint() {
  val hintRequest = HintRequest.Builder()
  .setPhoneNumberIdentifierSupported(true)
  .build()
  val intent = Auth.CredentialsApi.getHintPickerIntent(
    apiClient, hintRequest)
  startIntentSenderForResult(intent.getIntentSender(),
                             RESOLVE_HINT, null, 0, 0, 0)
}