Fix EZP-21005: When changing siteaccess, the autosave's preview is not updated

This issue affects Chrome on Mac. To detect a siteaccess change, the change
event is now used on the select, but in IE < 9, the change event does not
bubbled, as a result, this fix also removes the usage of event delegation to
not break this feature in IE.
(cherry picked from commit c9e83618ee9a7b95f64f21a5e99b9e886c494f7e)