docs: function elementOnloadDirective() {
          return {
              restrict: "A",
              scope: {
                  callback: "&ngOnload"
              },
              link: function link(scope, element, attrs) {
                  // hooking up the onload event - calling the callback on load event
                  element.one("load", function (_) {
                      var contentLocation = element.length > 0 && element[0].contentWindow ? element[0].contentWindow.location : undefined;
  
                      scope.callback({
                          contentLocation: contentLocation
                      });
                  });
              }
          };
      }