Code review comment for lp:~alan-griffiths/mir/even-NullWindowManager-configures-surface

I have to correct my earlier answer:

Although I had some tests using [Null|Skeleton]WindowManager at one point there no longer any on any active branch.

OTOH unity-system-compositor /src/window_manager.h derives from mir::shell::NullWindowManager and this use would be broken by making the class final.

The use in Unity8 is as described.

So, given the discussion this has provoked here I'm probably best just moving the code to the downstream projects.