[clang] [C++20][Modules] Fix crash when function and lambda inside loaded from different modules (PR #109167)

[Chuanqi Xu via cfe-commits]

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@@ -724,6 +724,9 @@ enum ASTRecordTypes {
 
   /// Record code for vtables to emit.
   VTABLES_TO_EMIT = 70,
+
+  /// Record code for the FunctionDecl to lambdas mapping.
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ChuanqiXu9 wrote:

Let's add some simple comments here to explain why we want to do this.

https://github.com/llvm/llvm-project/pull/109167