[clang] [Clang][P1061] Add stuctured binding packs (PR #121417)

[via cfe-commits]

https://github.com/cor3ntin commented:

Thanks a lot for this PR

First review pass.
I think the changes generally.
I'd like to see more tests. Notably
  - Check it works with pack indexing
  - BitField tests
  - Codegen tests
  - PCH/Module tests

There are unimplemented bits (ASTDumper/JSONDumper)  - you should have warnings for unhandled enumerator in switch

https://github.com/llvm/llvm-project/pull/121417