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

The new tests cover the new functionality completely. And what you don't see in the diff is existing test `slow_client_framerate_matches_compositor' covering off any potential for performance regressions really well (it took quite some effort to make that test pass).

Of course more tests always help. But AFAIK we're at 100% functionality coverage here already so it shouldn't be a blocking issue. All pre-existing tests still pass too.