Remove SO_BINDTODEVICE from VPN protect

SO_BINDTODEVICE is not needed with policy routing.
SO_BINDTODEVICE was also used on the default iface which causes problems
when the default iface is IPv6 only and the socket tries to connect to a
IPv4 address.

Bug: 12940882
Change-Id: I5b2bde0ac5459433fc5749f509072a548532f730

services/core/java/com/android/server/ConnectivityService.java

@@ -3567,8 +3567,7 @@ public class ConnectivityService extends IConnectivityManager.Stub {
             int user = UserHandle.getUserId(Binder.getCallingUid());
             if (ConnectivityManager.isNetworkTypeValid(type) && mNetTrackers[type] != null) {
                 synchronized(mVpns) {
-                    mVpns.get(user).protect(socket,
+                    mVpns.get(user).protect(socket);
-                            mNetTrackers[type].getLinkProperties().getInterfaceName());
                 }
                 return true;
             }