Self test appears to depend on some protocols

I noticed that the self test needs a way to create a surface, and bind a seat.

I'd think the self tests would make sense as a way to ensure the compositor can properly receive requests and send events (using a roundtrip and wl_callback) and ensuring the registry behaves properly.

I'd think the test that a surface can be made would be better placed inside of the wl_compositor tests?

Start by examining the self test and the existing wl_compositor tests, then trace where surface creation, seat binding, roundtrip, wl_callback, and registry checks are performed. Done means the self tests focus on receiving requests and sending events, while the surface-creation check is covered by the wl_compositor tests.

Written by the indexing model from the issue text.