GitLab

This CL:
(1) Moves SmartLock's enabled and allowed preferences to the
    MultiDeviceSetup service (see go/cros-multidevice-prefs).
(2) Renames existing preferences so that they are named in the same
    format.
(3) Removes some of these preferences from the settings whitelist,
    since they are not edited in settings.

Note: This CL unblocks adding enterprise policies to
FeatureStateManager, which must have access to the preferences.

TBR=stevenjb@chromium.org

Bug: 870113, 824568
Change-Id: Icffa4ed6b80095dd51e53b30a352289f584deba7
Reviewed-on: https://chromium-review.googlesource.com/1186033
Commit-Queue: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Reviewed-by: Maksim Ivanov <emaxx@chromium.org>
Reviewed-by: Ryan Hansberry <hansberry@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585932}