[clang-tools-extra] [clang] NFCI: Use `FileEntryRef` for `FileID` creation (PR #67838)

[Ben Langmuir via cfe-commits]

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@@ -228,7 +228,7 @@ int main(int argc, const char **argv) {
 
     Tool.applyAllReplacements(Rewrite);
     for (const auto &File : Files) {
-      auto Entry = FileMgr.getFile(File);
+      auto Entry = FileMgr.getOptionalFileRef(File);
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benlangmuir wrote:

Another place we could use `getFileRef` and print the error message.

https://github.com/llvm/llvm-project/pull/67838