[clang] [clang-tools-extra] [clang] Make deprecations of some `FileManager` APIs formal (PR #110014)

[Ben Langmuir via cfe-commits]

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@@ -427,12 +427,8 @@ static void InitializeFileRemapping(DiagnosticsEngine &Diags,
     }
 
     // Create the file entry for the file that we're mapping from.
-    const FileEntry *FromFile =
-        FileMgr.getVirtualFile(RF.first, ToFile->getSize(), 0);
-    if (!FromFile) {
-      Diags.Report(diag::err_fe_remap_missing_from_file) << RF.first;
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benlangmuir wrote:

Nice catch

https://github.com/llvm/llvm-project/pull/110014