function AdaptiveCardFormatter() {
    _classCallCheck(this, AdaptiveCardFormatter);

    /** @private */
    this.amexCardFormatter = new _amex_card_formatter2['default']();
    /** @private */
    this.defaultCardFormatter = new _default_card_formatter2['default']();
    /** @private */
    this.formatter = this.defaultCardFormatter;
  }
AdaptiveCardFormatter will decide if it needs to use
{@link AmexCardFormatter} or {@link DefaultCardFormatter}.