[clang] [clang][serialization] Enable `ASTWriter` to work with `Preprocessor` only (PR #115237)

[Jan Svoboda via cfe-commits]

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@@ -661,8 +661,8 @@ class ASTWriter : public ASTDeserializationListener,
 
   /// Write a precompiled header for the given semantic analysis.
   ///
-  /// \param SemaRef a reference to the semantic analysis object that processed
-  /// the AST to be written into the precompiled header.
+  /// \param Subject The object that processed the input to be written into the
+  /// AST file.
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jansvoboda11 wrote:

Sounds good, I clarified the documentation a bit, WDYT now?

https://github.com/llvm/llvm-project/pull/115237