[clang] [clang-repl] Don't double-remove extern "C" decls from the IdResolver (PR #218129)

[Vassil Vassilev via cfe-commits]

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@@ -235,7 +235,9 @@ void IncrementalParser::CleanUpPTU(TranslationUnitDecl *MostRecentTU) {
       }
       for (NamedDecl *D : NamedDeclsToRemove) {
         List.remove(D);
-        S.IdResolver.RemoveDecl(D);
+        if (D->getDeclName().getFETokenInfo() && !D->getLangOpts().ObjC &&
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vgvassilev wrote:

Good point -- we should move that into a lambda to avoid code duplication.

https://github.com/llvm/llvm-project/pull/218129