[clang] [libcxx] [Clang] Implement CWG2369 "Ordering between constraints and substitution" (PR #102857)

[Younan Zhang via cfe-commits]

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@@ -1517,7 +1555,7 @@ substituteParameterMappings(Sema &S, NormalizedConstraint &N,
 static bool substituteParameterMappings(Sema &S, NormalizedConstraint &N,
                                         const ConceptSpecializationExpr *CSE) {
   MultiLevelTemplateArgumentList MLTAL = S.getTemplateInstantiationArgs(
-      CSE->getNamedConcept(), CSE->getNamedConcept()->getLexicalDeclContext(),
+      CSE->getNamedConcept(), CSE->getNamedConcept()->getDeclContext(),
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zyn0217 wrote:

This is another leftover of my previous changes on `getTemplateInstantiationArgs()`... Will revert it

https://github.com/llvm/llvm-project/pull/102857