[1/2] Base: recover last location state during on/off switch

Based on this SlimRoms commit:
https://gerrit.slimroms.net/#/c/1421

Settings: https://gerrit.omnirom.org/#/c/4875/

Change-Id: Ia2484c9266d0276fd2d8bd0dc160487422e6063d
SettingsProvider: allow TETHER_DUN_REQUIRED to be overwritten

Allow overwriting of the default TETHER_DUN_REQUIRED value with
the build property 'ro.telephony.tetherdunrequired'

Recognized values are:
0 for not enforced
1 for enforced
2 for undefined (default; behaves as enforced)

Change-Id: I77c87230b54418ee5c385e5a7effd304a9743990
Merge "[1/2] Base: recover last location state during on/off switch" into android-4.4
merge changes from Omni 4.4 into local branch

Conflicts:
	packages/SystemUI/src/com/android/systemui/statusbar/policy/LocationController.java

Change-Id: Ia72457fede3f5124ae53e6a19de01d5724b72bc5