Add notification observer on Mac

SineStriker

2023-12-27 88b5b56b6a67d93208eae3980af2f30da09dd8ae

 src/quick/quickwindowagent.cpp

@@ -32,12 +32,10 @@
            return false;
        }

        if (!d->setup(window, new QuickItemDelegate())) {
            return false;
        }
        d->setup(window, new QuickItemDelegate());
        d->hostWindow = window;

#ifdef Q_OS_WINDOWS
#if defined(Q_OS_WINDOWS) && QWINDOWKIT_CONFIG(ENABLE_WINDOWS_SYSTEM_BORDERS)
        d->setupWindows10BorderWorkaround();
#endif
        return true;