Code review comment for lp:~vanvugt/mir/ddouble

While descriptions of manual testing scenarios are interesting we all know that manual testing doesn't scale and we'll miss regressions.

Can we think of a way to automate any of this? Even if we need to define a new test category "test_needing_graphics_hardware"? (I know this problem existed before this MP but here's as good a place as any to discuss.)

It would be really nice to have something more than unit tests to prove the /system/ behavior is as intended, not just the buffer queue.