crashtesting: crash on layout of ooo107760-1.doc

this has begun crashing since...

commit 8f2dd1df
Author: Khaled Hosny <khaledhosny@eglug.org>
Date:   Wed Nov 2 23:52:06 2016 +0200

    "Enable the new text layout engine by default"

but its presumably blameless

Change-Id: I5d9bfcd3277ce6b71dce8dced6947ab38b12f148

sw/source/core/layout/flowfrm.cxx

@@ -587,6 +587,7 @@ void SwFlowFrame::MoveSubTree( SwLayoutFrame* pParent, SwFrame* pSibling )
         //SwSectionFrame::MergeNext removing the pParent we're trying to reparent
         //into
         FlowFrameJoinLockGuard aJoinGuard(pParent);
+        SwFrameDeleteGuard aDeleteGuard(pParent);
         pOldParent = CutTree( &m_rThis );
         bInvaLay = PasteTree( &m_rThis, pParent, pSibling, pOldParent );
     }

sw/source/core/layout/wsfrm.cxx

@@ -963,8 +963,11 @@ void SwContentFrame::Cut()
                         if( pTmp )
                             pTmp->InvalidatePrt_();
                     }
-                    pUp->Cut();
-                    SwFrame::DestroyFrame(pUp);
+                    if (!pUp->IsDeleteForbidden())
+                    {
+                        pUp->Cut();
+                        SwFrame::DestroyFrame(pUp);
+                    }
                 }
                 else
                 {