this would break too

accessible/public/nsIAccessibilityService.idl

@@ -47,7 +47,7 @@ interface nsIAccessibilityService : nsISupports
   nsIAccessible createHTMLImageAccessible(in nsISupports aFrame);
   nsIAccessible createHTMLListboxAccessible(in nsIDOMNode aNode, in nsISupports aPresShell);
 // new
-  nsIAccessible CreateHTMLObjectAccessible(in nsISupports aFrame);
+//  nsIAccessible CreateHTMLObjectAccessible(in nsISupports aFrame);
 // end new
   nsIAccessible createHTMLRadioButtonAccessible(in nsISupports aFrame);
   nsIAccessible createHTMLSelectOptionAccessible(in nsIDOMNode aNode, in nsIAccessible aAccParent, in nsISupports aPresShell);