[clang] [clang][Dependency Scanning] Report Exported Modules during Scanning (PR #137421)

[Qiongsi Wu via cfe-commits]

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@@ -115,6 +115,15 @@ struct ModuleID {
   }
 };
 
+struct ExtendedModuleID {
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qiongsiwu wrote:

The structure is renamed and its definition is moved into `struct ModuleDeps` for better context. 

> why not use a std::pair? It comes with operator overloads.

What is the advantage of using `std::pair` here? 

https://github.com/llvm/llvm-project/pull/137421