[clang] [clang] Implement CTAD for type alias template. (PR #77890)

[via cfe-commits]

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@@ -39,6 +40,7 @@
 #include "llvm/ADT/SmallBitVector.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/Casting.h"
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cor3ntin wrote:

These new headers probably don't need to be added

https://github.com/llvm/llvm-project/pull/77890