STRING_LEN is the same as STRING_NOTFOUND

So use -1 here to realign logic to what it was before
35c24f9b6e. Though it
doesn't matter because aThesLookUpStr is going to be
empty in the case where we would examine the default
value of nDelimPos

Change-Id: I369c4e6903407b525dc0dcee9d507e90590eeb6b

sfx2/source/menu/mnumgr.cxx

@@ -138,7 +138,7 @@ PopupMenu* InsertThesaurusSubmenu_Impl( SfxBindings* pBindings, Menu* pSVMenu )
     pBindings->QueryState( SID_THES, pItem );
     OUString aThesLookUpStr;
     SfxStringItem *pStrItem = dynamic_cast< SfxStringItem * >(pItem);
-    sal_Int32 nDelimPos = STRING_LEN;
+    sal_Int32 nDelimPos = -1;
     if (pStrItem)
     {
         aThesLookUpStr = pStrItem->GetValue();