[clang] [clang] Trim large(-ish) includes from common headers (PR #216946)

[Chandler Carruth via cfe-commits]

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@@ -65,6 +65,7 @@
 #include "clang/Sema/Template.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/IR/DerivedTypes.h"
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chandlerc wrote:

See below for where it _is_ needed, but this was because my regex found something in a comment. Should be removed now.

https://github.com/llvm/llvm-project/pull/216946