xW: mark a footgun

These messages are used by IsDialogMessage(), and use the WM_USER range.

xW/xW.cpp

@@ -1723,6 +1723,9 @@ window_proc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 			break;
 		}
 		}
+	case DM_GETDEFID:
+	case DM_SETDEFID:
+		break;
 	}
 	return DefWindowProc(hWnd, uMsg, wParam, lParam);
 }