Remove Screen.parent hack in attachment and note
Those windows are using this hack from r35c7b4652253 to allow to switch view with changed record. This is because ra49c87646200 added a check on modified in Screen.switch_view for the Screen.default_row_activate. Indeed this check is only needed for the default_row_activate because other usage of Screen.switch_view are already checking for modified record (by asking to save or by preventing the switch).
The side effect of the parent hack on Attachment and Note is that the Screen doesn't re-display on group-changed. This breaks the change of states for the fields (like changing the attachment type doesn't make visible the link field).