fix(uiGridHeaderCell): Use hasClass() for IE9

IE9 doesn't support `classList`. Use angular.element's hasClass() instead.

Author: c0bra

Diff for: src/js/core/directives/ui-grid-column-menu.js

@@ -288,7 +288,7 @@ function ( i18nService, uiGridConstants, gridUtil ) {
 
       if ( menu.length !== 0 ){
         var mid = menu[0].querySelectorAll('.ui-grid-menu-mid'); 
-        if ( mid.length !== 0 && !mid[0].classList.contains('ng-hide') ){
+        if ( mid.length !== 0 && !angular.element(mid).hasClass('ng-hide') ) {
           myWidth = gridUtil.elementWidth(menu, true);
           $scope.lastMenuWidth = myWidth;
           column.lastMenuWidth = myWidth;