function testGetCountriesByIso2_multipleMatches() {
  var countries = firebaseui.auth.data.country.getCountriesByIso2('xk');
  var actualCodes = countries.map(function(country) {
    return country.e164_cc;
  });
  assertSameElements(['377', '381', '386'], actualCodes);
}
Tests that getCountriesByIso2 works correctly if multiple entries have the
same ISO2 code.