         
         var nSteps:uint = Math.abs(delta);
         var navigationUnit:uint;
+        var scrollPositionChanged:Boolean;
 
         // Scroll delta "steps".  
         navigationUnit = (delta < 0) ? NavigationUnit.RIGHT : NavigationUnit.LEFT;


package spark.components
{
import flash.events.MouseEvent;
import flash.geom.Point;


            if (!isNaN(hspDelta))
            {
                vp.horizontalScrollPosition += hspDelta;
                scrollPositionChanged = true;
                if (vp is IInvalidating)
                    IInvalidating(vp).validateNow();
            }
        }
        
        if (scrollPositionChanged)
            dispatchEvent(new Event(Event.CHANGE));

        event.preventDefault();
    }
    
