function loadByURL(url) {
    /* Load the icon from embedded data URL. */
    function loadByDataUrl(url) {
      var results = dataUrlRegex.exec(url);
      var isBase64 = /base64/i.test(url);
      var data = isBase64 ? window.atob(results[2]) : results[2];

      return $q.when(angular.element(data)[0]);
    }

    /* Load the icon by URL using HTTP. */
    function loadByHttpUrl(url) {
      return $q(function(resolve, reject) {
        // Catch HTTP or generic errors not related to incorrect icon IDs.
        var announceAndReject = function(err) {
            var msg = angular.isString(err) ? err : (err.message || err.data || err.statusText);
            $log.warn(msg);
            reject(err);
          },
          extractSvg = function(response) {
            if (!svgCache[url]) {
              svgCache[url] = angular.element('<div>').append(response)[0].querySelector('svg');
            }
            resolve(svgCache[url]);
          };

        $templateRequest(url, true).then(extractSvg, announceAndReject);
      });
    }

    return dataUrlRegex.test(url)
      ? loadByDataUrl(url)
      : loadByHttpUrl(url);
  }
Load the icon by URL (may use the $templateCache).
Extract the data for later conversion to Icon
@param {string} url icon URL
@returns {angular.$q.Promise}