fix(ui-sref-active): Use $scope.$evalAsync to apply css class

- Reduce digests caused by removing `$timeout` calls
- This seems to fix the broken behavior reported in both #2503 and #1997

Closes #2503
Closes #1997
Supercedes #2012

src/ng1/directives/stateDirectives.ts

@@ -461,14 +461,11 @@ let uiSrefActive = ['$state', '$stateParams', '$interpolate', '$transitions', '$
           }
 
           function addClass(el: IAugmentedJQuery, className: string) {
-            el.addClass(className);
-            $timeout(function () {
-              el.addClass(className);
-            });
+            $scope.$evalAsync(() => el.addClass(className));
           }
 
           function removeClass(el: IAugmentedJQuery, className: string) {
-            el.removeClass(className);
+            $scope.$evalAsync(() => el.removeClass(className));
           }
 
           function anyMatch(state: State, params: Obj) {