OzoneDisplay: Remove logic in DefaultDisplaySpec

This CL removes logic related to updating spec_ in OzoneDisplay as
we don't use it and upstream has completely removed it's usage. We need to
update our revision before removing DefaultDisplaySpec. This is part of an
effort to remove all DesktopScreen usage in OzoneDisplay

(cherry picked from commit 62b6e76890abdc6823b686cce1d710fe2d4510bb)
Backport parts of 08cd65ef and 7f2153f3.

The Chromium version we are tracking is past r251075, so we need to get rid
of SurfaceFactoryWayland::DefaultDisplaySpec() to fix the build with
compilers that accept the `override' keyword in methods.