Port "Option to hide Adb notification icon (1/2)"

Frameworks part is already in place

Change-Id: Ie65625305153b45012846f6d2250fb707c4eebfd
Settings: Forward port long-press-back to kill app (1/2)

Change-Id: I60f4b95eb9cc2ef6cf73a5f9317bca066e6bb901