Extensions using addStyleFile() does not enforce https/SSL URL

If I have a site supporting both http and https, I set my extensions URL to the http URL:

$civicrm_setting['URL Preferences']['extensionsURL'] = 'http://example.org/sites/example.org/extensions/';

However, if I use the following in an extension:

$resources = CRM_Core_Resources::singleton();
$resources->addStyleFile('ca.nodisys.example', 'example.css');

Then it will always include it with an absolute URL using http, not https, and therefore will not be visible in https. This is inconsistent with how the userFrameworkResourceURL variable is treated.