[clang] [clang-tools-extra] [Clang] Reland support friend declarations with a dependent nested-name-specifier (PR #208345)

[Oleksandr Tarasiuk via cfe-commits]

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a-tarasyuk wrote:

I initially tried to keep this PR scoped to template friend declarations that name members of dependent types and the access-control work needed for them... :) However, if it's acceptable to address additional CWG issues as part of this PR, I'm happy to do so - at least for some of them..

https://github.com/llvm/llvm-project/pull/208345