Fixes incorrect submit button detection.

framework/assets/yii.js

@@ -131,7 +131,7 @@ yii = (function ($) {
             if (method === undefined) {
                 if (action && action != '#') {
                     window.location = action;
-                } else if ($e.filter(':submit') && $form.length) {
+                } else if ($e.is(':submit') && $form.length) {
                     $form.trigger('submit');
                 }
                 return;