[clang] [Modules] [HeaderSearch] Don't reenter headers if it is pragma once (PR #76119)

[Volodymyr Sapsai via cfe-commits]

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@@ -1458,7 +1458,7 @@ bool HeaderSearch::ShouldEnterIncludeFile(Preprocessor &PP,
   } else {
     // Otherwise, if this is a #include of a file that was previously #import'd
     // or if this is the second #include of a #pragma once file, ignore it.
-    if ((FileInfo.isPragmaOnce || FileInfo.isImport) && !TryEnterImported())
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vsapsai wrote:

Technically, `TryEnterImported` can be inlined at another call site but I think it's not worth it and we can keep things the way you have in PR.

https://github.com/llvm/llvm-project/pull/76119