[Dillo-dev] setting image buffer and queueing resize

I had just fixed the dw simple image test that hadn't requested a resize when setting the imgbuf. And now I just found that one of the scaled2 test's images needs it as well. Perhaps we should make the resize argument to setBuffer() mandatory. But, better yet, how about if Image::setBuffer() just does a queueResize() if either of its dimensions are LENGTH_AUTO?