function testGetCountriesByE164Code_multipleMatches() {
  var countries = firebaseui.auth.data.country.getCountriesByE164Code('44');
  var actualKeys = countries.map(function(country) {
    return country.e164_key;
  });
  assertSameElements(['44-GG-0', '44-IM-0', '44-JE-0', '44-GB-0'], actualKeys);
}
Tests that getCountriesByE164Code works correctly if multiple entries have
the same e164_cc code.