ofz#4923 Divide-by-zero

Change-Id: I141884930c4f148f4d29a9a679642ab4b898bbc1
Reviewed-on: https://gerrit.libreoffice.org/47324Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

lotuswordpro/source/filter/lwpgrfobj.cxx

@@ -510,7 +510,7 @@ void LwpGraphicObject::CreateGrafObject()
                     fSclGrafWidth = fOrgGrafWidth;
                     fSclGrafHeight = fOrgGrafHeight;
                 }
-                else if (nScalemode & LwpLayoutScale::MAINTAIN_ASPECT_RATIO)
+                else if (nScalemode & LwpLayoutScale::MAINTAIN_ASPECT_RATIO && fOrgGrafHeight != 0.0 && fDisFrameHeight != 0.0)
                 {
                     if (fOrgGrafWidth/fOrgGrafHeight >= fDisFrameWidth/fDisFrameHeight)
                     {