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

            if (!isNaN(vspDelta))
            {
                vp.verticalScrollPosition += vspDelta;
                if (vp is IInvalidating)
                    IInvalidating(vp).validateNow();
            }
        }

        event.preventDefault();
    }
    


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

