[clang] Fix cycle in importing template specialization on auto type with typename (PR #162514)

[Shafik Yaghmour via cfe-commits]

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@@ -4058,7 +4059,13 @@ ExpectedDecl ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
   }
 
   Error Err = Error::success();
+  if (!UsedDifferentProtoType) {
+    Importer.DeclTypeCycles.insert(D);
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shafik wrote:

This make sense, that is why we have destructors so we don't have to manually manage these things.

https://github.com/llvm/llvm-project/pull/162514