Add syscall mach telemetry in the WebContent process on macOS to detect which are currently in use.
Pull request: https://github.com/WebKit/WebKit/pull/18023
Committed 268280@main (4d0e3132ca52): <https://commits.webkit.org/268280@main> Reviewed commits have been landed. Closing PR #18023 and removing active labels.
<rdar://problem/115866513>