[clang] Reland [C++20] [Modules] [Itanium ABI] Generate the vtable in the mod… (PR #102287)

[Chuanqi Xu via cfe-commits]

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@@ -790,6 +790,11 @@ class ASTReader
   /// the consumer eagerly.
   SmallVector<GlobalDeclID, 16> EagerlyDeserializedDecls;
 
+  /// The IDs of all vtables to emit. The referenced declarations are passed
+  /// to the consumers's HandleVTable eagerly after passing
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ChuanqiXu9 wrote:

Done

https://github.com/llvm/llvm-project/pull/102287