I'm surprised that this is all that is necessary here.  It won't work when bug 826249 lands, though. Then you'll also need to update the preview image.

Actually, I can't see how this works. What if the user has already cropped the image before rotating. What happens then?  I don't see you call edit() after the rotation, so how does the preview even get redrawn?  If you've converted to sepia and cropped, I'd expect this rotate() code to change back to a rotated full-size color photo.