[clang] [clang]: support std::meta::info for primitive types (PR #190356)

[via cfe-commits]

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@@ -5003,8 +5007,22 @@ void CXXNameMangler::mangleExpression(const Expr *E, unsigned Arity,
     goto recurse;
 
   case Expr::CXXReflectExprClass: {
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eiytoq wrote:

Nit: could you also add the corresponding grammar production comment for this new reflection mangling?

https://github.com/llvm/llvm-project/pull/190356