[clang] [APINotes] Upstream APINotesWriter (PR #65187)

[Saleem Abdulrasool via cfe-commits]

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@@ -33,6 +33,7 @@ class APINotesWriter::Implementation {
   /// Mapping from strings to identifier IDs.
   llvm::StringMap<IdentifierID> IdentifierIDs;
 
+public:
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compnerd wrote:

Why make all this public?

https://github.com/llvm/llvm-project/pull/65187