[llvm] [WPD] Change Devirt Cutoff to use DebugCounter (PR #170009)

[Mingming Liu via llvm-commits]

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mingmingl-llvm wrote:

My understanding of https://github.com/llvm/llvm-project/blob/24b87b8d4891d90afd8c4033a4997dedecbdd107/llvm/include/llvm/Support/DebugCounter.h#L156-L163

is that debug counter needs `-DLLVM_ENABLE_ASSERTIONS=ON`, and the test will need something like 'REQUIRES: asserts'.

https://github.com/llvm/llvm-project/pull/170009