Comment # 6 on bug 105317 from Timothy Arceri

Piglit test:

https://patchwork.freedesktop.org/patch/214341/

Mesa fix:

https://patchwork.freedesktop.org/patch/214346/

Note the WebGL test still froze in my testing but I think Firefox was
continuing to use my system mesa libs for some reason. The mesa patch fixes the
hang in the piglit test.