[clang] [Clang][Sema] Allow access to a public template alias declaration that refers to friend's private nested type (PR #83847)

[Younan Zhang via cfe-commits]

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@@ -259,6 +259,10 @@ Bug Fixes in This Version
   operator.
   Fixes (#GH83267).
 
+- Allow access to a public template alias declaration that refers to friend's
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zyn0217 wrote:

I suspect this should have been placed under the group `Bug Fixes to C++ Support`...?

https://github.com/llvm/llvm-project/pull/83847