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

[Younan Zhang via cfe-commits]

zyn0217 wrote:

Also, do you plan to fix https://github.com/llvm/llvm-project/issues/102320 in this or the follow-up patches?

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