CellBroadcast: Disable App links on wifi-only devices

PatchSet 2: Remove unnecessary check

Change-Id: I359b5fef2932dfa072b72384edf9ba730a1f71a1
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>
Add a quick SELinux mode toggle

There's no way to make it persistent, by design. This is purposefully
undocumented and meant to test policies at this stage.

Change-Id: Ic79ed773b199b68fee15f94acd2107a5ad20dc25

Conflicts:
	src/com/android/settings/DeviceInfoSettings.java