Code review comment for lp:~mir-team/mir/allow-lock-surf-orientation

I think that we ought to either change the MirOrientation values to bitflags or abstract out the necessary conversions.

*Needs Discussion*

I agree with Gerry that setting the "allowed orientations" is a request, not a requirement and that the shell could refuse.

I also wonder if this is something that should be set on the surface spec and applied at creation (or mutation) time rather than being an attribute on the surface that can be set at arbitrary times.