function buildDelayedToggler(navID) {
      return debounce(function() {
        // Component lookup should always be available since we are not using `ng-if`
        $mdSidenav(navID)
          .toggle()
          .then(function () {
            $log.debug("toggle " + navID + " is done");
          });
      }, 200);
    }
Build handler to open/close a SideNav; when animation finishes
report completion in console