[clang] [APINotes] Support nested tags (PR #99655)

[Saleem Abdulrasool via cfe-commits]

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@@ -421,9 +424,8 @@ struct Tag {
   std::optional<EnumConvenienceAliasKind> EnumConvenienceKind;
   std::optional<bool> SwiftCopyable;
   FunctionsSeq Methods;
+  TagsSeq Tags;
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compnerd wrote:

This would be confusing as the reader might expect all child tags to be here.

https://github.com/llvm/llvm-project/pull/99655