[clang] [llvm] [clang][deps] Cache `VFS::getRealPath()` (PR #68645)

[Ben Langmuir via cfe-commits]

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@@ -194,6 +201,17 @@ class DependencyScanningFilesystemSharedCache {
     const CachedFileSystemEntry &
     getOrInsertEntryForFilename(StringRef Filename,
                                 const CachedFileSystemEntry &Entry);
+
+    /// Returns real path associated with the filename or nullptr if none is
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benlangmuir wrote:

Nit: "the real path"

https://github.com/llvm/llvm-project/pull/68645