[clang] [WIP] [Modules] Delay reading type source info of the preferred_name attribute. (PR #122250)

[Ilya Biryukov via cfe-commits]

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@@ -337,6 +337,14 @@ class ASTRecordReader
   /// Reads attributes from the current stream position, advancing Idx.
   void readAttributes(AttrVec &Attrs);
 
+  /// Reads one attribute from the current stream position, advancing Idx.
+  /// Parent Decl is provided to delay attribute deserialization.
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ilya-biryukov wrote:

The lazy deserialization is a subtle difference, could we name the functions appropriately and "scary", e.g. `readAttrOrDelay`.

https://github.com/llvm/llvm-project/pull/122250