[clang] [Clang][Sema] Fix lookup of dependent operator= outside of complete-class contexts (PR #91498)

[Erich Keane via cfe-commits]

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@@ -1248,6 +1248,13 @@ static DeclContext *findOuterContext(Scope *S) {
   return nullptr;
 }
 
+static bool isDependentAssignmentOperator(DeclarationName Name,
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erichkeane wrote:

Ah, perhaps I was confusing... i'd like this inside the `namespace {`, now below.

https://github.com/llvm/llvm-project/pull/91498