Those were missed because xtro did not scan ObjC categories for
`objc_requires_super` attributes.
Fixing the naming mapping (to consider inlined categories) also
uncovered a few API with extraneous [DesignatedInitializer] attributes
Those were deprecated (API) and moved into categories so xtro missed
the designated initializer was removed.
All your `base`, well `super` in ObjC, now belong to us :)
https://github.com/xamarin/xamarin-macios/issues/3253
* Not every old annotations have been migrated (work in progress, to be completed in another PR);
* Sanitation of the data files (e.g. removal of dupes and fixed, by Apple, entries) is done, but not automated (also a work in progress)
Even then this is immediately useful, i.e. better merged before 15.6 gets branched.