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

[via cfe-commits]

cor3ntin wrote:

> I do not have a strong preference, but I kept `bindings()` the same since it represents the structure of the AST and that is how it is used in most places. (like 2x time more than `flat_bindings()`)

Lets not then

I'm inclined to say we should merge that once @zygoloid and @zwuis are happy their concerns are addressed
(+ more tests https://github.com/llvm/llvm-project/pull/121417/files#r1921058349)

We also need
  - A release note (clang/docs/ReleaseNotes.rst)
  - to update clang/www/cxx_status.html

We should hold off updating the feature test macro though.

WDYT?



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