forcepoint #30 check validity of group range

Change-Id: Ie0611f36809b051ce46030e44c137b4e1f8d2fe0
Reviewed-on: https://gerrit.libreoffice.org/51865Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Michael Stahl <Michael.Stahl@cib.de>

sc/source/core/data/column3.cxx

@@ -3089,6 +3089,8 @@ public:
                     xPrevGrp->mnLength += xCurGrp->mnLength;
                     pCur->SetCellGroup(xPrevGrp);
                     sc::formula_block::iterator itGrpEnd = it;
+                    if (xCurGrp->mnLength > std::distance(itGrpEnd, itEnd))
+                        throw css::lang::IllegalArgumentException();
                     std::advance(itGrpEnd, xCurGrp->mnLength);
                     for (++it; it != itGrpEnd; ++it)
                     {