[clang] [Clang][Sema] Refactor collection of multi-level template argument lists (PR #106585)

[Matheus Izvekov via cfe-commits]

mizvekov wrote:

Yep, I agree that the reduction indicates the original code was IFNDR.

We need a new reduction with no rename in order to locate this on QT code base and know for sure.

https://github.com/llvm/llvm-project/pull/106585