[llvm] [GlobalOpt] Handle operators separately when removing GV users (PR #84694)

[Eli Friedman via llvm-commits]

efriedma-quic wrote:

(I'm not exactly against killing off isLeakCheckerRoot, but last time we tried, it caused problems; see https://reviews.llvm.org/D69428 .)

https://github.com/llvm/llvm-project/pull/84694