This has to do with the fact, that you are trying to reuse the .user-error class, which is a "shim" for the CSS4 :user-error and shouldn't be triggered from script. The user-error scripts are loaded after onload or as soon as a user seems to interact with an invalid from.
From my point of view, you shouldn't use user-error and instead create your own class. You can simply check for validity using the ':invalid' selector:
$(this)[ $(this).is(':invalid') ? 'addClass' : 'removeClass']('invalid-value');
Simply write a function with similar code and bind them to events like change, input and so on and call it on start.
In case you still want to use user-error, you could do the following, but I would not recommend:
$.webshims.polyfill('forms');
//force webshims to load form-validation module as soon as possible
$.webshims.loader.loadList(['form-validation']);
//wait until form-validation is loaded
$.webshims.ready('DOM form-validation', function(){
$('input:invalid')
.filter(function(){
return !!$(this).val();
})
.trigger('refreshvalidityui')
;
});