Related: tdf#122081 null-deref of SwFootnoteFrame

load doc, ctrl+end, ctrl+home, ctrl+6 enter 29, return, wheel scroll
down 7 or 8 times and this null-deref

Change-Id: I1963a89e3223de89f3414e435accd8d8ebfe80a9
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/152511
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolan.mcnamara@collabora.com>
diff --git a/sw/source/core/text/txtftn.cxx b/sw/source/core/text/txtftn.cxx
index c86c1bc..035158e 100644
--- a/sw/source/core/text/txtftn.cxx
+++ b/sw/source/core/text/txtftn.cxx
@@ -664,7 +664,7 @@ void SwTextFrame::ConnectFootnote( SwTextFootnote *pFootnote, const SwTwips nDea
            mbInFootnoteConnect = false;
            return;
        }
        else if( pSrcFrame )
        else if (pSrcFrame && pFootnoteFrame)
        {
            SwFootnoteBossFrame *pFootnoteBoss = pFootnoteFrame->FindFootnoteBossFrame();
            if( !pFootnoteBoss->IsInSct() ||