minor change

Param/Node/INode.h

@@ -77,7 +77,7 @@ public:
     std::string displayName() const;
 
     //! Creates new parameter pool, with all local parameters and those of its children.
-    ParameterPool* createParameterTree() const;
+    virtual ParameterPool* createParameterTree() const override;
 
 private:
     const INode* m_parent{nullptr};