chromium/chrome/browser/ash/dbus/org.chromium.MetricsEventService.conf

<!DOCTYPE busconfig PUBLIC "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
  "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
<!--
  Copyright 2018 The Chromium Authors
  Use of this source code is governed by a BSD-style license that can be
  found in the LICENSE file.

  This file will be installed at /opt/google/chrome/dbus on Chromium OS.
-->
<busconfig>
  <policy user="chronos">
    <allow own="org.chromium.MetricsEventService"/>
  </policy>
</busconfig>