[clang] [clang] Implement provisional wording for CWG2398 regarding packs (PR #90820)

[via cfe-commits]

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@@ -2552,7 +2553,7 @@ DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams,
                         ArrayRef<TemplateArgument> As,
                         TemplateDeductionInfo &Info,
                         SmallVectorImpl<DeducedTemplateArgument> &Deduced,
-                        bool NumberOfArgumentsMustMatch) {
+                        bool NumberOfArgumentsMustMatch, bool Swapped) {
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cor3ntin wrote:

I think this needs a comment.
`Swapped` should be defaulted and have a better name.
Maybe `ForPartialOrderingOfDeducedTemplateTemplateArgument`

https://github.com/llvm/llvm-project/pull/90820