tdf#140537 scroll-wheeling shouldn't affect disabled scrollbars

Change-Id: I5d8659c7d431d35d628b12cebfe6a4b4f9cab9ef
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/111748
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
diff --git a/vcl/source/window/layout.cxx b/vcl/source/window/layout.cxx
index 1408a3d..ccdcc92 100644
--- a/vcl/source/window/layout.cxx
+++ b/vcl/source/window/layout.cxx
@@ -2051,7 +2051,10 @@
            const CommandWheelData* pData = rCEvt.GetWheelData();
            if( !pData->GetModifier() && ( pData->GetMode() == CommandWheelMode::SCROLL ) )
            {
                bDone = HandleScrollCommand(rCEvt, m_pHScroll, m_pVScroll);
                // tdf#140537 only handle scroll commands in the valid shown scrollbars
                bDone = HandleScrollCommand(rCEvt,
                                            m_pHScroll->IsVisible() ? m_pHScroll : nullptr,
                                            m_pVScroll->IsVisible() ? m_pVScroll : nullptr);
            }
        }
    }