code: private void addChangeListener(JavaScriptObject changeListener, String changeScope) {
  
          try {
              System.out.println("Adding native listener for scope " + changeScope);
              m_entityObserver.addEntityChangeListener(new CmsEntityChangeListenerWrapper(changeListener), changeScope);
          } catch (Exception e) {
  
              CmsDebugLog.getInstance().printLine("Exception occured during listener registration" + e.getMessage());
          }
      }
docs: Adds the change listener to the observer.<p>
  
  @param changeListener the change listener
  @param changeScope the change scope