[clang] [C++20][Modules][Serialization] Delay marking pending incomplete decl chains until the end of `finishPendingActions`. (PR #121245)

[Michael Park via cfe-commits]

mpark wrote:

> Presumably, we want to cherry pick that in clang 20?

Yeah, I'd think so if it's not too late.

https://github.com/llvm/llvm-project/pull/121245