[clang] [clang-tools-extra] [clang] improve class type sugar preservation in pointers to members (PR #130537)

[Matheus Izvekov via cfe-commits]

mizvekov wrote:

I had already done so, it's practically no change: https://llvm-compile-time-tracker.com/compare.php?from=cce9f360b50ca5a95d5cb550e27a8f6757423460&to=20841e444c0f8d48c6c9d34a77fe48164f7ae728&stat=instructions:u

https://github.com/llvm/llvm-project/pull/130537