[clang] [libcxx] [Clang] Add __common_type builtin (PR #99473)

[Nikolas Klauser via cfe-commits]

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@@ -6844,6 +6844,14 @@ CXXRecordMembersNamed(StringRef Name, Sema &S, QualType Ty) {
   return Results;
 }
 
+QualType Sema::getTypeMember(StringRef Name, QualType Type) {
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philnik777 wrote:

`CXXRecordMembersNamed` is used in `hasCStrMethod` below as well. Should I move all of this to `SemaType.cpp`?

https://github.com/llvm/llvm-project/pull/99473