[clang] [llvm] [llvm][NFC] Rework Timer.cpp globals to ensure valid lifetimes (PR #121663)

[Tarun Prabhu via llvm-commits]

https://github.com/tarunprabhu commented:

Thanks for working on this.

I have a couple of questions about inconsistent casing. Other than that, this looks reasonable to me. But I don't have a great deal of experience with this part of LLVM, so please wait for other reviewers.

https://github.com/llvm/llvm-project/pull/121663