[clang] [llvm] [STLForwardCompat] Implement llvm::type_identity (PR #146390)

[Jakub Kuderski via llvm-commits]

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@@ -36,6 +36,16 @@ template <typename T>
 using remove_cvref_t // NOLINT(readability-identifier-naming)
     = typename llvm::remove_cvref<T>::type;
 
+template <typename T>
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kuhar wrote:

Can you add a TODO comment to use the std:: version when we bump the C++ version?

https://github.com/llvm/llvm-project/pull/146390