 {
 
 import mx.core.ILayoutElement;
+import mx.core.IUIComponent;
 import mx.core.ScrollPolicy;
 
 import spark.components.Scroller;

            vsb.setLayoutBoundsSize(vsbW, Math.max(vsb.getMinBoundsHeight(), viewportH));
            vsb.setLayoutBoundsPosition(w - Math.max(minViewportInset, vsbW), minViewportInset);
        }
        
        target.setContentSize(w, h);
    }

}

}
            viewportH -= minViewportInset;
        if (!showVSB)
            viewportW -= minViewportInset;
        
        // Special case: viewport's size is explicitly set
        if (!isNaN(explicitViewportW))
            viewportW = explicitViewportW;
        if (!isNaN(explicitViewportH))
            viewportH = explicitViewportH;
        
        // layout the viewport
        if (viewport)
        {
