Code review comment for lp:~mir-team/mir/improve-attribute-protocol-and-normalize-getters

(4) Hmm, the protocol change uses "repeated" which actually appears to be backward compatible, so no ABI bump for libmirprotobuf is required after all;
https://developers.google.com/protocol-buffers/docs/proto#updating

(5) This single-use function doesn't need to exist. If you initialize your variables in the constructor then it's more obvious locking isn't required either...
ms::BasicSurface::initialize_attributes()

(6) I think the TODO comment is still valid and should not be deleted:
395 - /*
396 - * TODO: In future, query the shell implementation for the subset of
397 - * attributes/types it implements.
398 - */

Needs^H^H^H^H^HWants fixing, somewhat. I haven't gone back through in enough detail to approve yet but won't block any more.