Move app sidebar to BaseStatusBar for use in both PhoneStatusBar and TabletStatusBar.

Change-Id: I6296623b88a91489743c1734e798099537b0b57d

Conflicts:
	packages/SystemUI/src/com/android/systemui/statusbar/BaseStatusBar.java
	packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBar.java