fix qt5 build

Zhao Yuhang

2023-12-14 ca6ba7d7aa547b4e0c8d86fb9e00f25374a181db

 src/widgets/widgetwindowagent_p.h

@@ -17,9 +17,13 @@
        // Host
        QWidget *hostWidget{};

        std::unique_ptr<QObject> paintFilter;
#ifdef Q_OS_WINDOWS
        void setupWindows10BorderWorkaround();
#elif defined(Q_OS_MACOS)
        void setupMacOSTitleBar(QWidget *titleBar);
#endif
    };

}

#endif // WIDGETWINDOWAGENTPRIVATE_H
#endif // WIDGETWINDOWAGENTPRIVATE_H