[clang] Add code completion for C++20 keywords. (PR #107982)

[Younan Zhang via cfe-commits]

zyn0217 wrote:

> I am not sure which section I should add in clang/docs/ReleaseNotes.rst? There isn't a section related to code completion.

@16bit-ykiko There is an individual file for clang-tools-extras `clang-tools-extra/docs/ReleaseNotes.rst` which covers changes in clangd. See also https://github.com/llvm/llvm-project/pull/105975.

(AFAICT, for a long time, clangd hasn't had a practice for updating its release notes whenever new features are implemented, but the situation is getting improved recently.)


https://github.com/llvm/llvm-project/pull/107982