[clang] [clang] Allow trivial pp-directives before C++ module directive (PR #153641)

[Erich Keane via cfe-commits]

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@@ -3099,7 +3099,7 @@ class Preprocessor {
   bool setDeserializedSafeBufferOptOutMap(
       const SmallVectorImpl<SourceLocation> &SrcLocSeqs);
 
-  /// Whether allow C++ module directive.
+  /// Whether seen pp-directives which may change the preprocessing state.
----------------
erichkeane wrote:

```suggestion
  /// Whether we've seen pp-directives which may have changed the preprocessing state.
```

https://github.com/llvm/llvm-project/pull/153641