[CrOS MultiDevice] Add metrics for feature states.

MultiDevice.BetterTogetherSuite.MultiDeviceFeatureState
AndroidSms.MultiDeviceFeatureState
SmartLock.MultiDeviceFeatureState
InstantTethering.MultiDeviceFeatureState

Multiple enumerated histograms with the same 9 buckets:
1) “Prohibited by policy”,
2) “Disabled by user”,
3) “Enabled by user”,
4) “Not supported by Chromebook”,
5) “Not supported by phone”,
6) “Unavailable, no verified host”,
7) “Unavailable, insufficient security”,
8) “Unavailable, suite disabled”, and
9) “Further setup required”.

Bug: 870138
Change-Id: Ic96b673a10b4ecd52b9f44b0f29abc52d29858b3
Reviewed-on: https://chromium-review.googlesource.com/c/1315938
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: Ryan Hansberry <hansberry@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Commit-Queue: Regan Hsu <hsuregan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#607804}
4 files changed