SystemUI: improve circle battery

While plugged in, the circle animation would cause the statusbar to
keep redrawing itself repeatedly, using up unnecessary cpu cycles,
even when idle.

- Removed circle animation in status bar
- Left animations on keyguard/notificaiton header
- Set layer type to hardware when animating for optimized quick drawing
- Cleaned up some logic and unnecessary locking
- Removed extra work done in each draw
- override onDraw instead of draw to let the View system decide when we
  should draw

CYNGNOS-1583

Change-Id: If0624ab6e3723f4522ebbd9ce583b142c1cb4606
Signed-off-by: Roman Birg <roman@cyngn.com>