Use light sensor signal to enter and exit dozing.

Use device light sensor to signal when to enter low-light mode (AOD),
instead of a timeout.

Video: https://photos.app.goo.gl/w7cpArEhyiEtvm7g9

Change-Id: I525b62216496c710f4edabdef46fc4d817d16c39
Test: manual
2 files changed