check authentication on page which doesn't reload (#14573)

mandayejs/do_login.js

@@ -147,4 +147,8 @@ page.open(input.address, function(status) {
       else
           $(input.form_submit_element).click();
   }, input);
+
+    if (page.injectJs(input.auth_checker)) {
+        timer = setInterval(check_auth, 100, page);
+    }
 });