New VpnInfoPreference created to control the presence or absence
of the warning icon based on the vpn type.
The VpnPreferenceController type casts the preference based on
whether the provider model is enabled. It also detects legacy vpns
by using the LegacyVpnProfileStore, and comparing VPN profile
usernames with the active VPN config's user.
note: because of the junit test migration, I will add test
files in a separate CL
Screenshot: https://screenshot.googleplex.com/AfGrH8wRusTvbf4
Test: atest -c SettingsUnitTests
Bug: Bug: 176821216
Change-Id: I1aa93be5b90b404d9d9cb9bf47ea76fdc9aad401
