replace Session.WaitUntilClosed() by a context

interface.go

@@ -1,6 +1,7 @@
 package quic
 
 import (
+	"context"
 	"io"
 	"net"
 	"time"
@@ -56,9 +57,9 @@ type Session interface {
 	RemoteAddr() net.Addr
 	// Close closes the connection. The error will be sent to the remote peer in a CONNECTION_CLOSE frame. An error value of nil is allowed and will cause a normal PeerGoingAway to be sent.
 	Close(error) error
-	// WaitUntilClosed() blocks until the session is closed.
+	// The context is cancelled when the session is closed.
 	// Warning: This API should not be considered stable and might change soon.
-	WaitUntilClosed()
+	Context() context.Context
 }
 
 // A NonFWSession is a QUIC connection between two peers half-way through the handshake.