Fix "Turn on phone calls" for guest user

Move "Turn on phone calls" from guest detail user screen to user screen.
Optimisation: Applying restrictions to default guest user has been moved
to UserManagerService -> setDefaultGuestRestrictions.

Following UX there is no need for confirmation dialog.

Bug: 191483069
Test: make RunSettingsRoboTests -j128 ROBOTEST_FILTER="com.android.settings.users.GuestTelephonyPreferenceControllerTest"
       make RunSettingsRoboTests -j128 ROBOTEST_FILTER="com.android.settings.users.UserSettingsTest"
Change-Id: Id7391d3f85954ea7f9c94791f24174105ec8073e

tests/robotests/src/com/android/settings/users/UserSettingsTest.java

@@ -146,6 +146,8 @@ public class UserSettingsTest {
         mFragment = spy(new UserSettings());
         ReflectionHelpers.setField(mFragment, "mAddUserWhenLockedPreferenceController",
                 mock(AddUserWhenLockedPreferenceController.class));
+        ReflectionHelpers.setField(mFragment, "mGuestTelephonyPreferenceController",
+                mock(GuestTelephonyPreferenceController.class));
         ReflectionHelpers.setField(mFragment, "mMultiUserTopIntroPreferenceController",
                 mock(MultiUserTopIntroPreferenceController.class));
         ReflectionHelpers.setField(mFragment, "mUserManager", mUserManager);