[clang] In ExprRequirement building, treat OverloadExpr as dependent (PR #66683)

[via cfe-commits]

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@@ -9063,7 +9063,8 @@ Sema::BuildExprRequirement(
     concepts::ExprRequirement::ReturnTypeRequirement ReturnTypeRequirement) {
   auto Status = concepts::ExprRequirement::SS_Satisfied;
   ConceptSpecializationExpr *SubstitutedConstraintExpr = nullptr;
-  if (E->isInstantiationDependent() || ReturnTypeRequirement.isDependent())
+  if (E->isInstantiationDependent() || E->getType()->isPlaceholderType() ||
+      ReturnTypeRequirement.isDependent())
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cor3ntin wrote:

I've been trying to think about whether checking `UnresolvedLookupExpr` would make more sense but
I think what you have works in all cases.

https://github.com/llvm/llvm-project/pull/66683