fixing bug 114956 - Crashed on OK to prefs changing all labels text. r=bienvenu, sr=sspitzer, a=asa

mailnews/base/src/nsMsgDBView.cpp

@@ -342,6 +342,8 @@ NS_IMETHODIMP nsMsgDBView::Observe(nsISupports *aSubject, const char *aTopic, co
 
     if(matchFound) {
       NS_ENSURE_SUCCESS(rv,rv);
+      NS_ASSERTION(mOutliner, "no outliner, see bug #114956");
+      if(mOutliner)
         mOutliner->Invalidate();
     }
   }
@@ -1759,6 +1761,8 @@ NS_IMETHODIMP nsMsgDBView::DoCommand(nsMsgViewCommandTypeValue command)
     if (!mIsSearchView)  //ignore for search view
     {
       rv = ExpandAll();
+      NS_ASSERTION(mOutliner, "no outliner, see bug #114956");
+      if(mOutliner)
         mOutliner->Invalidate();
     }
     break;
@@ -1766,6 +1770,8 @@ NS_IMETHODIMP nsMsgDBView::DoCommand(nsMsgViewCommandTypeValue command)
     if (!mIsSearchView)  //ignore for search view
     {
       rv = CollapseAll();
+      NS_ASSERTION(mOutliner, "no outliner, see bug #114956");
+      if(mOutliner)
         mOutliner->Invalidate();
     }
     break;