alid) {   std::unique_ptr<net::DnsClient> tmp = mock_dns_.CreateDnsClient();   net::DnsClient* dns_client = tmp.get();   LogDnsClient log_client(std::move(tmp), net::NetLogWithSource(), 0);    // Get the current DNS config, modify it and broadcast the update.   net::DnsConfig config(*dns_client->GetConfig());   ASSERT_