port some more code (for os < win10)

Yuhang Zhao

2023-12-05 9b1599d82e86d2d0463b60fe6fa61f94be50f983

 src/core/contexts/win32windowcontext_p.h

@@ -33,6 +33,9 @@
        bool snapLayoutHandler(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam,
                               LRESULT *result);

        bool customWindowHandler(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam,
                                 LRESULT *result);

    protected:
        WId windowId = 0;