BatteryStatsViewer UI improvements:

1. DEVICE and ALL_APPS are now combined in one screen
2. Totals are displayed at the top
3. Column headers are shown conditionally
4. New icon for totals
5. Swipe-to-refresh

Bug: 187370721
Test: mp :BatteryStatsViewer && adb shell am start -n com.android.frameworks.core.batterystatsviewer/.BatteryConsumerPickerActivity

Change-Id: Ic250fe54b3fe3c54ff461218f126fc83f9921fd9