control/testapi.c: Detach event that was originally attached.

src/control/testapi.c

@@ -242,7 +242,7 @@ static void test_events (const char ** argv, int argc)
     libvlc_event_send (em, &event);
     assert( !callback_was_called );
 
-    libvlc_event_detach (em, mi_events[i], test_events_callback_and_detach, &callback_was_called, &ex);
+    libvlc_event_detach (em, mi_events[mi_events_len-1], test_events_callback_and_detach, &callback_was_called, &ex);
     catch ();
 
     log ("+ Testing regular detach()\n");