dashboard/lib/templates/directives/sort-th.html

<div ng-click="toggleOrder()" class="table-order">
  <span ng-transclude></span>
  <span ng-show="asc && on" class="glyphicon glyphicon-chevron-up"></span>
  <span ng-show="!asc && on" class="glyphicon glyphicon-chevron-down"></span>
</div>