code: function createSite(refInfo) {
    let url = parseUrl(refInfo.referer);
    let result = {
      'domain': url.hostname,
      'page': url.protocol + '://' + url.hostname + url.pathname
    };
    if (self === top && document.referrer) {
      result.ref = document.referrer;
    }
    let keywords = document.getElementsByTagName('meta')['keywords'];
    if (keywords && keywords.content) {
      result.keywords = keywords.content;
    }
    return result;
  }
docs: Creates site description object