[clang] [C++20][Modules] Improve namespace look-up performance for modules. (PR #171769)

[Aiden Grossman via cfe-commits]

boomanaiden154 wrote:

We (Google) are seeing more breakage from this patch. I have another case where a translation unit is showing a lot of new `error: no member named 'redacted_foo' in the global namespace` errors. Going to work on a reproducer, but it might take a while.

https://github.com/llvm/llvm-project/pull/171769