Specify notification types for Auto Hide statusbar (1/2)

Allows users to choose between "non-permanent only" and "all notifications" in the autohide
the statusbar when there are no notifications check.

- cleanup a bit
- reduce method and provider settings call

Change-Id: I1f793df1ab702e89cdfeee8faa915ff13a3cc782

Conflicts:

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

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