[clang] [clang-tools-extra] [Clang] support friend declarations with a dependent nested-name-specifier (PR #191268)

[Yanzuo Liu via cfe-commits]

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@@ -170,7 +170,7 @@ class X {
   // FIXME: this is ill-formed, because A<T>::B::C does not end with a simple-template-id
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zwuis wrote:

We can remove it.

https://github.com/llvm/llvm-project/pull/191268