code: function registerLocaleData(data, localeId, extraData) {
      if (typeof localeId !== 'string') {
          extraData = localeId;
          localeId = data[0 /* LocaleId */];
      }
      localeId = localeId.toLowerCase().replace(/_/g, '-');
      LOCALE_DATA[localeId] = data;
      if (extraData) {
          LOCALE_DATA[localeId][19 /* ExtraData */] = extraData;
      }
  }
docs: Register global data to be used internally by Angular. See the
  ["I18n guide"](guide/i18n#i18n-pipes) to know how to import additional locale data.
  
  @experimental i18n support is experimental.
   The signature registerLocaleData(data: any, extraData?: any) is deprecated since v5.1