[1/2] Base: Battery Bar

Port of https://github.com/AOKP/frameworks_base/commit/e5d25fd7d7c2c9342d1088f4a96831b2aac89751

Change-Id: I69549320440ae679368bfa87c7f36d0d0734d51c

Conflicts:
	packages/SystemUI/res/values/attrs.xml