[clang-tools-extra] [clangd] Avoid type erasure for local recursive callbacks (PR #203042)

[Aleksandr Platonov via cfe-commits]

https://github.com/ArcsinX approved this pull request.

Thanks, LGTM.
But let's wait a couple of days before landing this, to make sure nobody has objections.

https://github.com/llvm/llvm-project/pull/203042