This setting is OEM upstream requirement for mobile data
preferred apps feature.
Bug: 171872461
Test: atest FrameworksNetTests
Change-Id: Ic5e0515b2b948de3d333c8d8e073d0b15514562a
Have getter/setter methods for external modules that can
get/set the setting values.
Bug: 182538166
Test: atest FrameworksNetTests
Change-Id: I82225a43f95e3e1d3e52c4e7a0fc541c0087292e
Add more connectivity module settings and update all references
to ConnectivitySettingsManager.
Bug: 182538166
Test: atest FrameworksNetTests
Change-Id: Ie96fbd0996ed3acb37099b6270bf3d4c2e558e9a