[Provider Model] Internal cleanup - remove Provider Model flag and deprecated legacy UI part.3

Test: atest DefaultSubscriptionControllerTest, NetworkProviderSettingsTest
Bug: 197066557
Change-Id: I7d29b58ca5476ae0bb6fe2e04fecb96164cb1ada

src/com/android/settings/network/VpnPreferenceController.java

@@ -156,7 +156,7 @@ public class VpnPreferenceController extends AbstractPreferenceController
             summary = getNameForVpnConfig(vpn, UserHandle.of(uid));
         }
         // Optionally add warning icon if an insecure VPN is present.
-        if (Utils.isProviderModelEnabled(mContext) && mPreference instanceof VpnInfoPreference) {
+        if (mPreference instanceof VpnInfoPreference) {
             final int insecureVpnCount = getInsecureVpnCount();
             boolean isInsecureVPN = insecureVpnCount > 0;
             ((VpnInfoPreference) mPreference).setInsecureVpn(isInsecureVPN);