Do not prevent element processing when date_popup field is 'hidden'.

I use the Working hours field type that has a couple of date_popup elements in it. I use field_access to remove access to the field for certain roles. Normally this should prevent the modification of the field, but in my situation, whenever I save the node with the field, and there is no field access, I got integrity constraint violation, because the field was not processed and the value was not correctly set. There are a couple of places where the processing is short-circuited and this makes some sense, since there is javascript that would be attached, when it doesn't need to be attached:

function date_popup_element_process($element, &$form_state, $form) {
  if (date_hidden_element($element)) {
     return $element;
  }

function date_popup_validate($element, &$form_state) {

  if (date_hidden_element($element)) {
    return;
  }

But this changes what the value is in my situation where the date_popup is hidden, because of #access, but I still need it to be processed. As a result I get:
PDOException: SQLSTATE[HY000]: General error: 1366 Incorrect integer value: '' for column 'field_opening_hours_from'

I think the solution would be not to stop processing but maybe just to prevent the attaching of js/css, so to prevent the call to date_popup_add(), but also there are the settings being added in date_popup_js_settings_id(). Maybe the best approach would be to convert all js/css loading to #attached, which would automatically make sure they don't get added, unless element is rendered.