[clang] [Clang] Do not create dependent CallExpr having UnresolvedLookupExpr inside non-dependent context (PR #124609)

[Shafik Yaghmour via cfe-commits]

https://github.com/shafik commented:

I have a few concerns w/ this PR.

Number one we do not cover the original test case which crashes, as far as I can tell none of the tests crash before this fix. This is large oversight.

It looks like currently gcc is the only one that rejects this code as we will now do as well: https://godbolt.org/z/Pqnb4eq6K

I don't see anyone justifying this change in behavior w/ wording from the standard. I would have expected to see such wording references in the summary and also added to a comment in the code itself to document the justification for this change in behavior for future readers of the code.

CC @erichkeane @mizvekov @AaronBallman 

https://github.com/llvm/llvm-project/pull/124609