Created attachment 7709 FIx patch The attached patch does just that =)
Created attachment 7710 Fix patch Oops, now the patch is the correct one.
Andre Miranda referenced this bugreport in commit 3dc74db98805b49958623d9f04715b091aa928c5 Make more former GtkStock strings translatable (Bug #14379) https://git.xfce.org/xfce/xfce4-panel/commit?id=3dc74db98805b49958623d9f04715b091aa928c5
Annoying oversight when porting away from GtkStock... Thanks for the patch!