[clang] [clang][DependencyScanning] Track dependencies from prebuilt modules to determine IsInStableDir (PR #132237)

[Cyndy Ishida via cfe-commits]

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@@ -237,6 +237,17 @@ class ASTReaderListener {
     return true;
   }
 
+  /// Overloaded member function of \c visitInputFile that should
+  /// be defined when the input file contains both the virtual and external
+  /// paths, for example when deserializing input files from AST files.
+  ///
+  /// \returns true to continue receiving the next input file, false to stop.
+  virtual bool visitInputFile(StringRef FilenameAsRequested,
+                              StringRef ExternalFilename, bool isSystem,
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cyndyishida wrote:

Is it worth documenting whats the intended difference between `Filename` vs `FilenameAsRequested`? Or is the docstring already enough? 

https://github.com/llvm/llvm-project/pull/132237