Guard Notification Panel against DISABLE2_NOTIFICATION_SHADE

- Guard StatusManagerService.togglePanel() and expandNotificationsPanel() against DISABLE2_NOTIFICATION_SHADE
- Fix bug in StatusBar.disable()
- Fix longPressOnHomeBehaviorToString() for dumpsys

Bug: 175044947
Test: Simple boot check and checked the added logic is in the right
execution path

Change-Id: Id922977e52eb1f09d57f14b7a0c443785d444a52