tdf#172325: Crash when toggling "Use CJK manuscript grid" (take 2)

I tried to understand the mayhem of notification/broadcast and finally gave up.
After more searching, I found that we can lock the view and that's why I used.
I hope it doesn't bring some regression but at least QA tests seem ok.

Change-Id: I067703e2c7cacd884548f768c4f2d983975a1d99
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/207477
Reviewed-by: Julien Nabet <serval2412@yahoo.fr>
Tested-by: Jenkins

sw/source/ui/config/optload.cxx

@@ -700,7 +700,13 @@ bool SwLoadOptPage::FillItemSet( SfxItemSet* rSet )
         if ( m_pWrtShell )
         {
             SwDoc* pDoc = m_pWrtShell->GetDoc();
+            // tdf#172325: this part broadcast changes and if there's the WriterInspector enabled
+            // it goes mayhem in SfxItemSet management
+            // so perhaps it's just a workaround but feel free to revert the lock/unlock call
+            // if you find a better way
+            m_pWrtShell->LockView(true);
             pDoc->SetDefaultPageMode( bIsSquaredPageModeFlag );
+            m_pWrtShell->LockView(false);
             m_pWrtShell->SetModified();
         }
         bRet = true;