Fix TabUI Notification icon layout.

Notifications were getting cut-off on bottom when System bar
re-sized.

Change-Id: I8268aa21ec0ca1c1601940f3f2c09b8eed9d47b8
Signed-off-by: Zaphod <mwilson@acesappraisal.com>

Conflicts:
	packages/SystemUI/res/layout/system_bar_notification_area.xml