Fixing itemRenderer memory leak in AdvancedDataGrid on columns change

Please read the discussion about memory leak here.

I think I found the workaround for this issue. We need to override the set columns method in a extended ADG class and add the code to free the dictionary holding on to the itemRenderers. Here is the code.

<?xml version="1.0" encoding="utf-8"?>
<mx:AdvancedDataGrid xmlns:mx="http://www.adobe.com/2006/mxml">
 <mx:Script>
  <![CDATA[
   override public function set columns(value:Array):void
   {
    super.columns = value;
    itemRendererToFactoryMap = new Dictionary(false);
   }
  ]]>
 </mx:Script>
</mx:AdvancedDataGrid>