[clang] [clang-tools-extra] [Clang] Add a builtin that deduplicate types into a pack (PR #106730)

[Ilya Biryukov via cfe-commits]

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@@ -36,6 +40,7 @@
 #include "clang/Sema/TemplateDeduction.h"
 #include "clang/Sema/TemplateInstCallback.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/Casting.h"
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ilya-biryukov wrote:

Done.

https://github.com/llvm/llvm-project/pull/106730