SettingsLib: refactor for extensibility.

Add short version of charging / discharging labels. Extended getBatteryInfo method to take in additional flag for short version labels.

Change-Id: I499ce59493f1345c3084d48829ded5117d470e44
(cherry picked from commit e686bf4514d9c1116a4eaa8af285f44613e23b36)
3 files changed