net/http: update bundled http2

Updates x/net/http2 to git rev 8a52c78 for golang.org/cl/23258
(http2: fix Transport.CloseIdleConnections when http1+http2 are wired together)

Fixes #14607

Change-Id: I038badc69e230715b8ce4e398eb5e6ede73af918
Reviewed-on: https://go-review.googlesource.com/23280
Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/net/http/clientserver_test.go

@@ -1196,6 +1196,35 @@ func TestH12_AutoGzipWithDumpResponse(t *testing.T) {
 	}.run(t)
 }
 
+// Issue 14607
+func TestCloseIdleConnections_h1(t *testing.T) { testCloseIdleConnections(t, h1Mode) }
+func TestCloseIdleConnections_h2(t *testing.T) { testCloseIdleConnections(t, h2Mode) }
+func testCloseIdleConnections(t *testing.T, h2 bool) {
+	defer afterTest(t)
+	cst := newClientServerTest(t, h2, HandlerFunc(func(w ResponseWriter, r *Request) {
+		w.Header().Set("X-Addr", r.RemoteAddr)
+	}))
+	defer cst.close()
+	get := func() string {
+		res, err := cst.c.Get(cst.ts.URL)
+		if err != nil {
+			t.Fatal(err)
+		}
+		res.Body.Close()
+		v := res.Header.Get("X-Addr")
+		if v == "" {
+			t.Fatal("didn't get X-Addr")
+		}
+		return v
+	}
+	a1 := get()
+	cst.tr.CloseIdleConnections()
+	a2 := get()
+	if a1 == a2 {
+		t.Errorf("didn't close connection")
+	}
+}
+
 type noteCloseConn struct {
 	net.Conn
 	closeFunc func()

src/net/http/export_test.go

@@ -24,7 +24,6 @@ var (
 	ExportErrRequestCanceled     = errRequestCanceled
 	ExportErrRequestCanceledConn = errRequestCanceledConn
 	ExportServeFile              = serveFile
-	ExportHttp2ConfigureTransport = http2ConfigureTransport
 	ExportHttp2ConfigureServer   = http2ConfigureServer
 )
 
@@ -152,3 +151,12 @@ func hookSetter(dst *func()) func(func()) {
 		*dst = fn
 	}
 }
+
+func ExportHttp2ConfigureTransport(t *Transport) error {
+	t2, err := http2configureTransport(t)
+	if err != nil {
+		return err
+	}
+	t.h2transport = t2
+	return nil
+}

src/net/http/h2_bundle.go

@@ -50,6 +50,18 @@ type http2ClientConnPool interface {
 	MarkDead(*http2ClientConn)
 }
 
+// clientConnPoolIdleCloser is the interface implemented by ClientConnPool
+// implementations which can close their idle connections.
+type http2clientConnPoolIdleCloser interface {
+	http2ClientConnPool
+	closeIdleConnections()
+}
+
+var (
+	_ http2clientConnPoolIdleCloser = (*http2clientConnPool)(nil)
+	_ http2clientConnPoolIdleCloser = http2noDialClientConnPool{}
+)
+
 // TODO: use singleflight for dialing and addConnCalls?
 type http2clientConnPool struct {
 	t *http2Transport
@@ -250,6 +262,15 @@ func http2filterOutClientConn(in []*http2ClientConn, exclude *http2ClientConn) [
 	return out
 }
 
+// noDialClientConnPool is an implementation of http2.ClientConnPool
+// which never dials.  We let the HTTP/1.1 client dial and use its TLS
+// connection instead.
+type http2noDialClientConnPool struct{ *http2clientConnPool }
+
+func (p http2noDialClientConnPool) GetClientConn(req *Request, addr string) (*http2ClientConn, error) {
+	return p.getClientConn(req, addr, http2noDialOnMiss)
+}
+
 func http2configureTransport(t1 *Transport) (*http2Transport, error) {
 	connPool := new(http2clientConnPool)
 	t2 := &http2Transport{
@@ -302,15 +323,6 @@ func http2registerHTTPSProtocol(t *Transport, rt RoundTripper) (err error) {
 	return nil
 }
 
-// noDialClientConnPool is an implementation of http2.ClientConnPool
-// which never dials.  We let the HTTP/1.1 client dial and use its TLS
-// connection instead.
-type http2noDialClientConnPool struct{ *http2clientConnPool }
-
-func (p http2noDialClientConnPool) GetClientConn(req *Request, addr string) (*http2ClientConn, error) {
-	return p.getClientConn(req, addr, http2noDialOnMiss)
-}
-
 // noDialH2RoundTripper is a RoundTripper which only tries to complete the request
 // if there's already has a cached connection to the host.
 type http2noDialH2RoundTripper struct{ t *http2Transport }
@@ -5054,7 +5066,7 @@ func (t *http2Transport) RoundTripOpt(req *Request, opt http2RoundTripOpt) (*Res
 // connected from previous requests but are now sitting idle.
 // It does not interrupt any connections currently in use.
 func (t *http2Transport) CloseIdleConnections() {
-	if cp, ok := t.connPool().(*http2clientConnPool); ok {
+	if cp, ok := t.connPool().(http2clientConnPoolIdleCloser); ok {
 		cp.closeIdleConnections()
 	}
 }