Clock: use mCalendar to get seconds

We haz teh calendar already. No need to create a new one to get the seconds.

Change-Id: Iccfc6e25367ad57a99bf27c29311e260b5e276d8
Signed-off-by: Tianrui Guo <tianrui@pac-rom.com>
Avoid incorrect clock layout when using both am/pm & seconds

Change-Id: I8cf34a9fb9f03d33d2d84b4ae735526fa81feda3

Conflicts:
	packages/SystemUI/src/com/android/systemui/statusbar/policy/Clock.java