code: public void createPiiToken(
              @NonNull final String personalId,
              @NonNull final TokenCallback callback) {
          createPiiToken(personalId, mDefaultPublishableKey, null, callback);
      }
docs: The simplest way to create a PII token. This runs on the default
  {@link Executor} and with the currently set {@link #mDefaultPublishableKey}.
  
  @param personalId the personal id used to create this token
  @param callback a {@link TokenCallback} to receive either the token or an error