Original change description follows:
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Implement issue #3326435: Battery stats improvements
Keep track of discharge while screen is on vs. off.
Checkin looks like:
5,0,u,dc,1,1,1,0
The last four numbers are, from left:
- Maximum battery drain over time period.
- Minimum battery drain over time period.
- Battery drain while screen was on.
- Battery drain while screen was off.
Change-Id: Ie3cfe52df29b3f28ba8dc3350abe6cc967c76324
9248e95a2f