Update third_party/closure_compiler/externs/metrics_private.js

$ tools/json_schema_compiler/generate_all_externs.py

Change-Id: I1bd33c93038b353180badef86e2b73512a3def98
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7277245
Auto-Submit: Victor Vianna <victorvianna@google.com>
Commit-Queue: Steven Bennetts <stevenjb@chromium.org>
Commit-Queue: Victor Vianna <victorvianna@google.com>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1560804}
NOKEYCHECK=True
GitOrigin-RevId: ddd43ac0236eeb8b6dd28b209a0ed63174f1702d