fb: post time-critical systemui flags to window manager

thanks Kiril for this suggestion. We are already using window
manager for other things in immersive mode....so nice addition
to fix a race condition

Change-Id: I5d818214d7864014fa77c0d562d2908110d93303
fb: add back small bottom margin 1px

2px was to much 0 was to less.....1 seems to be perfect

Change-Id: Iefa3aee39197786da1652c3b372aa46c0ea3a6dc
Merge remote-tracking branch 'github/kk4.4' into slimkk

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