[clang-tools-extra] [clang] remove ClassScopeFunctionSpecializationDecl (PR #66636)

[Aaron Ballman via cfe-commits]

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@@ -1481,10 +1481,6 @@ enum DeclCode {
   /// template template parameter pack.
   DECL_EXPANDED_TEMPLATE_TEMPLATE_PARM_PACK,
 
-  /// A ClassScopeFunctionSpecializationDecl record a class scope
-  /// function specialization. (Microsoft extension).
-  DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION,
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AaronBallman wrote:

I verify that we already bumped the AST serialization version number, so older serialized code should no longer expect to deserialize.

https://github.com/llvm/llvm-project/pull/66636