There are a few remaining classes that need to be wrapped properly when bridged to objective-c. These are the ones that did not get fixed in bug 8331. They are DOMRGBColor, DOMRect, and DOMCounter, and I'm sure that it would be a straight-forward fix, and i'm just missing something. I'm attaching a patch in case someone wants to look at what i tried (it doesn't work), and possibly shed some light on this.
Created attachment 8477 [details] broken patch - why doesn't it work?
More info on why this doesn't work would be helpful (failed compile? test case fails?). I think the issue is that you need to implement the xxxWith: methods for the classes in question.
These have all been fixed by now.