Huh? It appears they did test it, and for that matter (according to the linked post) so did the Nouveau devs who also found it failed the easily accessible test suite.
We agree Nouveau is completely blacklisted right? That's the main problem here.
And the test suite failed on a minor issue where the cause was uncertain, which gets in the way of checking for the bigger definitely-the-driver problem.
That's the reason I have webgl disabled even though I'm on Windows with a supported driver. It opens a gaping security/DoS hole without any benefit (do you ever see webgl used in any website?)