Just noticed that the Script I linked to will be thrown by Strokes set to something other than Align > Inside.
But including checks for that would likely be a bother as the Shape Layer Strokes seem not to be iincluded in the DOM, so one would have to, if possible at all, get the information from ActionDesriptor-code or one could evaluate the PathPoints instead of the Layer’s Bounds.
If the task is a vey frequent one for you you could ask for help with a Scripting solution over at
http://forums.adobe.com/community/photoshop/photoshop_scripting
