[llvm] [nfc][thinlto] Factor common state for `computeImportForModule` (PR #65427)

[Mircea Trofin via llvm-commits]

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@@ -370,6 +370,29 @@ class GlobalsImporter final {
   }
 };
 
+/// Determine the list of imports and exports for each module.
+class ModuleImportsScheduler final {
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mtrofin wrote:

`Manager` then.

https://github.com/llvm/llvm-project/pull/65427