Code review comment for lp:~raof/mir/xserver-spawner

(1) "er" issues as described above.

(2) I'm concerned about mentioning "X"-anything in the Mir source too. It feels like we're preventing Mir from being a success in its own right if it even has to mention X in its source. Even if the coupling is weak, we should strive for a better answer. Generalize, move it out-of-project, etc. We almost certainly don't want an "X" namespace. That's a reasonable indication that we're going in the wrong direction.

(3) You've introduced a build-dep on libx11-dev:
  +#include <X11/Xlib.h>
Definitely don't do that, at least :)