add WIP mac imp

Zhao Yuhang

2023-12-13 2a1e707b1cf530b00a5c0f3766466f10bd617619

 src/widgets/widgetwindowagent_p.h

@@ -16,6 +16,10 @@

        // Host
        QWidget *hostWidget{};

#ifdef Q_OS_WINDOWS
        void setupWindows10BorderWorkaround();
#endif
    };

}