[clang] [libcxx] [clang] Preserve Qualifiers and type sugar in TemplateNames (PR #93433)

[Nikita Popov via cfe-commits]

nikic wrote:

This change seems to have some compile-time overhead. I'm not seeing a lot on CTMark, but during the clang bootstrap there are many files with ~1% regressions (http://llvm-compile-time-tracker.com/compare_clang.php?from=ec8fe598a94d2826f8e4f79367a5a45a6b32d284&to=9c4a716c1292096fcbdf415b63b7b0122b03310f&stat=instructions%3Au&sortBy=interestingness). Just an FYI in case this is unexpected.

https://github.com/llvm/llvm-project/pull/93433