[clang] [clang] Document the type_visibility attribute (PR #79157)

[Aaron Ballman via cfe-commits]

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@@ -3220,8 +3220,8 @@ def TypeVisibility : InheritableAttr {
   let Args = [EnumArgument<"Visibility", "VisibilityType",
                            ["default", "hidden", "internal", "protected"],
                            ["Default", "Hidden", "Hidden", "Protected"]>];
-//  let Subjects = [Tag, ObjCInterface, Namespace];
-  let Documentation = [Undocumented];
+  let Subjects = SubjectList<[Tag, ObjCInterface, Namespace], ErrorDiag>;
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AaronBallman wrote:

I would separate out this change because it's not really related to documenting the attribute (this is used to generate automatic checks for the subject, so it corresponds to this code that was manually written and can possibly be removed: https://github.com/llvm/llvm-project/blob/091fc81d485594d4b751c10518230769c905430c/clang/lib/Sema/SemaDeclAttr.cpp#L2917)

https://github.com/llvm/llvm-project/pull/79157