Resolves: tdf#150273 use same bg as valueset

Change-Id: Idbe4bf6eaad64fdd0865a2734b4c9d0221801df9
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/142401
Tested-by: Caolán McNamara <caolanm@redhat.com>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
diff --git a/svtools/source/control/ctrlbox.cxx b/svtools/source/control/ctrlbox.cxx
index dbfcf84..414c07a8 100644
--- a/svtools/source/control/ctrlbox.cxx
+++ b/svtools/source/control/ctrlbox.cxx
@@ -1575,6 +1575,8 @@ void SvtLineListBox::UpdatePreview()
        const auto nPos = (aVirDev->GetOutputSizePixel().Height() - aImage.GetSizePixel().Height()) / 2;
        aVirDev->Push(vcl::PushFlags::MAPMODE);
        aVirDev->SetMapMode(MapMode(MapUnit::MapPixel));
        const StyleSettings& rSettings = Application::GetSettings().GetStyleSettings();
        aVirDev->SetBackground(rSettings.GetFieldColor());
        aVirDev->Erase();
        aVirDev->DrawImage(Point(0, nPos), aImage);
        m_xControl->set_image(aVirDev.get());