followup to add http server close method

pkg/proxy/userspace/proxier_test.go

@@ -23,6 +23,7 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"os"
 	"strconv"
 	"sync/atomic"
 	"testing"
@@ -85,16 +86,17 @@ func waitForClosedPortUDP(p *Proxier, proxyPort int) error {
 var tcpServerPort int32
 var udpServerPort int32
 
-func init() {
+func TestMain(m *testing.M) {
 	// Don't handle panics
 	runtime.ReallyCrash = true
 
 	// TCP setup.
-	// TODO: Close() this when fix #19254
 	tcp := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
 		w.Write([]byte(r.URL.Path[1:]))
 	}))
+	defer tcp.Close()
+
 	u, err := url.Parse(tcp.URL)
 	if err != nil {
 		panic(fmt.Sprintf("failed to parse: %v", err))
@@ -124,6 +126,11 @@ func init() {
 	}
 	udpServerPort = int32(udpServerPortValue)
 	go udp.Loop()
+
+	ret := m.Run()
+	// it should be safe to call Close() multiple times.
+	tcp.Close()
+	os.Exit(ret)
 }
 
 func testEchoTCP(t *testing.T, address string, port int) {