SL-14270 A bit of cleanup #3

Just in case and for clarity

indra/llui/llfolderviewmodel.cpp

@@ -52,11 +52,13 @@ LLFolderViewModelItemCommon::~LLFolderViewModelItemCommon()
 {
     // Children don't belong to model, but to LLFolderViewItem, just mark them as having no parent
     std::for_each(mChildren.begin(), mChildren.end(), [](LLFolderViewModelItem* c) {c->setParent(NULL); });
+    mChildren.clear();
 
     // Don't leave dead pointer in parent
     if (mParent)
     {
         mParent->removeChild(this);
+        mParent = NULL;
     }
 }
 

indra/newview/llconversationmodel.h

@@ -156,6 +156,7 @@ class LLConversationItemSession : public LLConversationItem
 public:
 	LLConversationItemSession(std::string display_name, const LLUUID& uuid, LLFolderViewModelInterface& root_view_model);
 	LLConversationItemSession(const LLUUID& uuid, LLFolderViewModelInterface& root_view_model);
+	virtual ~LLConversationItemSession() {}
 
 	/*virtual*/ bool hasChildren() const;
     LLPointer<LLUIImage> getIcon() const { return NULL; }