code: function (node) {
        var current = node;
        while (current) {
          if ((current.$mdGesture || {})[this.name]) {
            return current;
          }
          current = current.parentNode;
        }
        return null;
      }
docs: Find and return the nearest parent element that has been registered to listen for this handler via $mdGesture.register(element, 'handlerName').