[clang-tools-extra] [include-cleaner] Make sure exports of stdlib also works for physical files (PR #72246)

[Haojian Wu via cfe-commits]

================
@@ -232,6 +232,17 @@ class PragmaIncludes::RecordPragma : public PPCallbacks, public CommentHandler {
   void checkForExport(FileID IncludingFile, int HashLine,
                       std::optional<Header> IncludedHeader,
                       OptionalFileEntryRef IncludedFile) {
+    auto AddExport = [&] {
+      auto ExportingFileName = SM.getFileEntryForID(IncludingFile)->getName();
+      if (IncludedFile) {
----------------
hokein wrote:

if we inline the lambda, we just need these two `if`s, and `ExportingFileName` would be `Top.Path`. 

https://github.com/llvm/llvm-project/pull/72246