[clang] [Clang][Sema] Fix an ICE where structured binding packs within a lambda were not added to the CapturingScopeInfo (PR #214716)

[Yanzuo Liu via cfe-commits]

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@@ -366,6 +366,7 @@ features cannot lower the translation-unit ABI level;
 - Fixed USR generation for declarations whose signature mentions a class-type
   non-type template parameter. (#GH212351)
 - Clang now defines the GCC-compatible predefined macro `__SIG_ATOMIC_TYPE__`. (#GH213895)
+- Fixed an ICE when declaring a structured binding pack inside a lambda. (#GH214160)
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zwuis wrote:

This is misleading. The problem is not wrongly declaring a structured binding pack, but wrongly expanding the pack.

> ... We can describe what the crash reproducer wants to do like 'where the structured binding packs are expanded outside where they are declared'.

Update: outside _the lambda_ where they are declared

https://github.com/llvm/llvm-project/pull/214716