Floating window (1/2)
This is the popup code from Paranoid Android's HALO, which has already been commited. This commit just allows it to be on or off as some users may not want to use this function. We have a better idea on how to use this functionaility which will be seen later.

For now though, this is the messy way of turning it on and off.

Signed-off-by: Paul Beeler <sparksco@gmail.com>
Fix Floating Window

Change-Id: Icf48df5d6ffbfb8e6b16a632f5135a0fa02dd946
Halo: Add master switch to disable Halo (1/2)

Signed-off-by: Paul Beeler <sparksco@gmail.com>

Fix build
Signed-off-by: Paul Beeler <sparksco@gmail.com>
Reworked transparent layer
When a halo'ed window is opened, the transparent layer will be always visible. It will manage the background dim.
This fixes some apps dimming its sandboxed processes (like chrome).

LayerActivity manages its own lifecycle. When it's focused after paused it finishes itself.

System processes (identified by "android" pkg in SystemUI and system uid in Activity) don't use the layer and still use their own background. This
has been kept this way to not interfere with their activity.

Signed-off-by: Paul Beeler <sparksco@gmail.com>
LayerActivity: Corrected lifecycle
Should contemplate the case that the activity gets stopped
Fix little derp causing visual bug

To reproduce, disable halo, and press "clear all notifications" button

Change-Id: Ice7ab62229e27db53ef51fd5df55dbcd0a86358b
HALO cleanup

Signed-off-by: Paul Beeler <sparksco@gmail.com>