don't call getOutputString when we are not using the result, tdf#92802

Change-Id: I5569eb618b5577714bd10c77ade198638394df8b
Reviewed-on: https://gerrit.libreoffice.org/20725
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Markus Mohrhard <markus.mohrhard@googlemail.com>
diff --git a/sc/source/filter/xml/xmlcelli.cxx b/sc/source/filter/xml/xmlcelli.cxx
index f55e570..9d691ed 100644
--- a/sc/source/filter/xml/xmlcelli.cxx
+++ b/sc/source/filter/xml/xmlcelli.cxx
@@ -1331,7 +1331,7 @@ void ScXMLTableRowCellContext::AddNonFormulaCell( const ScAddress& rCellPos )

    if( nCellType == util::NumberFormat::TEXT )
    {
        if( cellExists(rCellPos) && CellsAreRepeated() )
        if( !bIsEmpty && !maStringValue && !mbEditEngineHasText && cellExists(rCellPos) && CellsAreRepeated() )
            pOUText.reset( getOutputString(rXMLImport.GetDocument(), rCellPos) );

        if (!mbEditEngineHasText && !pOUText && !maStringValue)