[clang] [llvm] [Clang][PCH] Use metadata for embedding AST (PR #214135)

[Alexis Engelke via cfe-commits]

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

LGTM, but I'm not excited about the approach (I don't have a better idea, though). Please wait for a few days before merging in case there are further comments.

https://github.com/llvm/llvm-project/pull/214135