[clang] [Clang][P1061] Add stuctured binding packs (PR #121417)

[Richard Smith via cfe-commits]

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@@ -951,28 +959,124 @@ Sema::ActOnDecompositionDeclarator(Scope *S, Declarator &D,
   return New;
 }
 
+// CheckBindingsCount
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zygoloid wrote:

We [don't start function comments with the function name](https://llvm.org/docs/CodingStandards.html#commenting:~:text=Don%E2%80%99t%20duplicate%20function%20or%20class%20name%20at%20the%20beginning%20of%20the%20comment.). (We used to but that's an old style we're phasing out.)

https://github.com/llvm/llvm-project/pull/121417