So Settings app will block user accessing restricted settings
if OEM config is off.
Bug: 217709978
Test: With OEM config on, accessibility page for unknown source app is
disabled by default.
Test: With OEM config off, accessibility page for unknown source app is
not disabled.
Change-Id: Id25e8fd76e6192fd4db64f81903449bb02785b39
* Need to be used in 'Connected device' page for hearing aid device
Bug: 225117933
Bug: 227172850
Test: make RunSettingsRoboTests ROBOTEST_FILTER=RestrictedPreferenceHelperTest
Change-Id: Icda456aa9c7597dc113775d1359acb0a8430768c