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- This disables the feature by default
- Updates tests based on changed feature state
- Fixes a race condition checking the sensor status via powerd
- Support for ambient EQ is now going to be gated on a cros config value
  because some devices have the sensor but can't support the feature
- The cros config value will enable the feature only on explicitly
  supported devices
- This is a partial revert of [1] which can't be cleanly reverted
  because the pref value on unsupported devices may have already
  been set

[1] - https://chromium-review.googlesource.com/c/chromium/src/+/1974815

BUG=1034068,1036038,1036546
TEST=NightLightTest.*,manual

Change-Id: If51ec1b6a8ae787fb64b89f2f536eec0087b09af
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1992183Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Reviewed-by: Bailey Berro <baileyberro@chromium.org>
Commit-Queue: Zentaro Kavanagh <zentaro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#730247}