coverity#1000600 Division or modulo by float zero

Change-Id: If39679b54ef1bb0a7af794c2f7a6186ebd69c2e0

writerfilter/source/dmapper/DomainMapperTableManager.cxx

@@ -741,8 +741,14 @@ void DomainMapperTableManager::endOfRowAction()
         sal_Int16 nLastRelPos = 0;
         sal_uInt32 nBorderGridIndex = m_nGridBefore;
 
+        size_t nWidthsBound =  m_nCell.back( ) - 1;
+        if (nWidthsBound)
+        {
+            if (nFullWidthRelative == 0)
+                throw std::range_error("divide by zero");
+
             ::std::vector< sal_Int32 >::const_iterator aSpansIter = pCurrentSpans->begin( );
-        for( sal_uInt32 nBorder = 0; nBorder < m_nCell.back( ) - 1; ++nBorder )
+            for( sal_uInt32 nBorder = 0; nBorder < nWidthsBound; ++nBorder )
             {
                 double fGridWidth = 0.;
                 for ( sal_Int32 nGridCount = *aSpansIter; nGridCount > 0; --nGridCount )
@@ -756,6 +762,7 @@ void DomainMapperTableManager::endOfRowAction()
                 nLastRelPos = nLastRelPos + nRelPos;
                 ++aSpansIter;
             }
+        }
         TablePropertyMapPtr pPropMap( new TablePropertyMap );
         pPropMap->Insert( PROP_TABLE_COLUMN_SEPARATORS, uno::makeAny( aSeparators ) );