[clang] [clang] NFCI: Use `FileEntryRef` in `SourceManager::FileInfos` (PR #67742)

[Ben Langmuir via cfe-commits]

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@@ -179,6 +179,46 @@ TEST(FileEntryTest, DenseMapInfo) {
     EXPECT_TRUE(Set.find(R1)->isSameRef(R1));
     EXPECT_TRUE(Set.find(R2)->isSameRef(R2));
   }
+
+  // Insert R1Also second and confirm R1 "wins" when looked up as FileEntry.
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benlangmuir wrote:

This comment looks like it's for the other test case.  R1Also is inserted first and it wins here.

https://github.com/llvm/llvm-project/pull/67742