Sorry, it should be:

 

 

Here is the code:

 

// get the cute editor instance
var editor1 = document.getElementById('CE_Editor1_ID');
var editor = document.getElementById('CE_Editor1_ID');

if(editor.all)
{
    var lis=editor.all.tags("LI");
      for(var i=0;i<lis.length;i++)
      {
           var item=lis.item(i);
           if(item._IsTreeDropDown=="True")
           {
            //put your code here        
           }
      }
}