tdf#120786: show undocked toolbar only when it's ready

in SetAlwaysOnTop set window flags only, don't show the widget yet
(it'll be shown later, when it can be painted in full)

Change-Id: I5e855f1ebba1eb9985744ece055a0f141e965940
Reviewed-on: https://gerrit.libreoffice.org/67739
Reviewed-by: Katarina Behrens <Katarina.Behrens@cib.de>
Tested-by: Katarina Behrens <Katarina.Behrens@cib.de>
(cherry picked from commit ad6d9bce1126997750d3c3c2606d28164d63d1d8)
Reviewed-on: https://gerrit.libreoffice.org/69124
Reviewed-by: Xisco Faulí <xiscofauli@libreoffice.org>
Tested-by: Xisco Faulí <xiscofauli@libreoffice.org>
diff --git a/vcl/qt5/Qt5Frame.cxx b/vcl/qt5/Qt5Frame.cxx
index 3537c1b..acf7c6d 100644
--- a/vcl/qt5/Qt5Frame.cxx
+++ b/vcl/qt5/Qt5Frame.cxx
@@ -613,7 +613,6 @@ void Qt5Frame::SetAlwaysOnTop(bool bOnTop)
        pWidget->setWindowFlags(flags | Qt::CustomizeWindowHint | Qt::WindowStaysOnTopHint);
    else
        pWidget->setWindowFlags(flags & ~(Qt::CustomizeWindowHint | Qt::WindowStaysOnTopHint));
    pWidget->show();
}

void Qt5Frame::ToTop(SalFrameToTop nFlags)