fb: enable navbar for hw key devices

we moved this part into PhoneWindowManager which controlls the navbar.
Due that we allow on all devices a navbar the check on PhoneStatusBar
is not needed and prevend the navbar on comming up on hw key devices

Change-Id: Ia3aef15389007cba1b3905b5de9f084578b4aca3

Conflicts:

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