[libc-commits] [libc] [libc][wchar] implement wcslen (PR #124150)

[Nick Desaulniers via libc-commits]

nickdesaulniers wrote:

ah sorry @RossComputerGuy , [631a6e0](https://github.com/llvm/llvm-project/commit/631a6e0004e57ca85569b99ea411418627925697) winded up with me as the author and github as the committer, because I used the `gh` command line util to merge. My intent was for you to be the author of record and myself to be the committer of record.  My apologies.  If you feel strongly; I can revert+reland with this corrected, though it is churn.

https://github.com/llvm/llvm-project/pull/124150