Work around #242 (not a real fix, but better than nothing).
This only gets rid of the wrong code in vu_scale_getrect, so that the vu meter is rendered correctly in gop again. The only downside is that this allows the scale to extend past the gop rectangle. But that's better than having the wrong stuff drawn in the gop IMHO.
NOTE: The scale of the vu meter is still slightly off, don't know how to fix that.