Use doIpv6Provisioning in testPref64Option. am: a8a73c53

        ByteBuffer pref64 = new StructNdOptPref64(prefix, 600).toByteBuffer();

        ByteBuffer ra = buildRaPacket(pio, rdnss, pref64);

        waitForRouterSolicitation();

        mPacketReader.sendResponse(ra);

        // The NAT64 prefix might be detected before or after provisioning success.

        // Don't test order between these two events.

        ArgumentCaptor<LinkProperties> captor = ArgumentCaptor.forClass(LinkProperties.class);

        verifyWithTimeout(null /*inOrder*/, mCb).onProvisioningSuccess(captor.capture());

        LinkProperties lp = doIpv6OnlyProvisioning(null /*inOrder*/, ra);

        expectAlarmSet(null /*inOrder*/, "PREF64", 600);

        reset(mCb, mAlarm);

        // From now on expect events in order.

        InOrder inOrder = inOrder(mCb, mAlarm);

        LinkProperties lp = captor.getValue();

        if (lp.getNat64Prefix() != null) {

            assertEquals(prefix, lp.getNat64Prefix());

        } else {