fb: Change density on the fly

Change-Id: I7ee16d32ee882fea22367f49f69f4da744f3aa45

Conflicts:
	core/java/android/content/res/Resources.java
	core/java/android/view/IWindowManager.aidl
	core/java/android/view/WindowManagerPolicy.java
	packages/SystemUI/src/com/android/systemui/statusbar/BaseStatusBar.java
	packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBar.java
	packages/SystemUI/src/com/android/systemui/statusbar/policy/KeyButtonView.java
	policy/src/com/android/internal/policy/impl/PhoneWindowManager.java
	services/java/com/android/server/wm/WindowManagerService.java