tdf#140506: fix repeated table header switching

this fixes regression from f899c28f210c6565b7227d7665d449f194d2af8e,
which asssumed all frames to be listening to the Notifier of the
format. That is not (yet) the case.

Change-Id: Ib684842c571823eeb72824196ccfdb1df8179e85
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/118370
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>
diff --git a/sw/source/core/docnode/ndtbl.cxx b/sw/source/core/docnode/ndtbl.cxx
index d6c37d2..6e44077 100644
--- a/sw/source/core/docnode/ndtbl.cxx
+++ b/sw/source/core/docnode/ndtbl.cxx
@@ -2904,9 +2904,9 @@ void SwDoc::SetRowsToRepeat( SwTable &rTable, sal_uInt16 nSet )
            std::make_unique<SwUndoTableHeadline>(rTable, rTable.GetRowsToRepeat(), nSet) );
    }

    rTable.SetRowsToRepeat(nSet);
    const SwMsgPoolItem aChg(RES_TBLHEADLINECHG);
    rTable.SetRowsToRepeat( nSet );
    rTable.GetFrameFormat()->GetNotifier().Broadcast(sw::LegacyModifyHint(&aChg, &aChg));
    rTable.GetFrameFormat()->CallSwClientNotify(sw::LegacyModifyHint(&aChg, &aChg));
    getIDocumentState().SetModified();
}