[clang] [clang] Fix the crash when dumping deserialized decls (PR #133395)

[Ilya Biryukov via cfe-commits]

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@@ -57,6 +59,8 @@ class ASTDeserializationListener {
   /// A module import was read from the AST file.
   virtual void ModuleImportRead(serialization::SubmoduleID ID,
                                 SourceLocation ImportLoc) {}
+  /// The deserialization of the AST file was finished.
+  virtual void FinishedDeserializing() {}
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ilya-biryukov wrote:

Yes, I saw that. But in any case you probably want the other callback too.
Having both callbacks would allow to add assertions about the invariants implementation expect. E.g. my concerns about reentrancy could be expressed as `bool IsDeserializing` field and a few assertions.

https://github.com/llvm/llvm-project/pull/133395