This is the final switch for using accelerated compositing on WinCairo. There are a few problems that should be looked into before doing this switch. WebGL doesn't render to the screen anymore, there are some crashes (especially when using html5 video elements), and I'm not sure how to change the TextureMapper accelerated compositing settings on Windows.
Created attachment 222582 [details] Patch
I'm going to let https://bugs.webkit.org/show_bug.cgi?id=127833 cover this, unless they decide otherwise.