title: Flex: Wrapper for ResourceManager.getInstance().getString is not notified of localeChain updates
body: <p>I have written a utility library that contains some of my most used functions. 
  There I have a wrapper for ResourceManager.getString to simplify using the resource manager in non-UI classes:</p>
  
  <pre><code>package
  {
      import mx.resources.ResourceManager;
      /**
       * Convenience function to return a localized string
       * */
      [Bindable("change")]
      public function _s(bundle:String, resourceName:String):String
      {
          return (ResourceManager.getInstance().getString(bundle, resourceName));
      }
  }
  </code></pre>
  
  <p>The problem is, that when the localeChain is changed, the function won't get called, while when invoking <code>resourceManager.getString</code> everything works as expected.</p>
  
  <p>Since it is just a wrapper, I can easily switch back to the "long" notation, but I'm curious how I would achieve the desired behaviour.</p>