Error on legend widget on dynamic layer

I try to use the legend widget for my dynamic layer but get the error message on LegendWidgetLegendSkin.mxml
For some reason, FlexViewer 3.1 uncompiled one didn't have LegendWidgeLegendSkin.mxml. So I added it and I can view the legend on rest services URL. I attached the files. Hope someone know how to solve this. Thank you.

Attached Thumbnails

 

Attached Files

• Legend.zip‎ (7.6 KB)