don't use closures for passing OnLost and OnAcked STREAM frame callbacks (#3833)

internal/ackhandler/frame.go

@@ -27,3 +27,11 @@ func putFrame(f *Frame) {
 	f.OnAcked = nil
 	framePool.Put(f)
 }
+
+type StreamFrame struct {
+	Frame   *wire.StreamFrame
+	Handler interface {
+		OnLost(*wire.StreamFrame)
+		OnAcked(*wire.StreamFrame)
+	}
+}

internal/ackhandler/packet.go

@@ -11,6 +11,7 @@ import (
 type Packet struct {
 	SendTime        time.Time
 	PacketNumber    protocol.PacketNumber
+	StreamFrames    []StreamFrame
 	Frames          []*Frame
 	LargestAcked    protocol.PacketNumber // InvalidPacketNumber if the packet doesn't contain an ACK
 	Length          protocol.ByteCount
@@ -32,6 +33,7 @@ var packetPool = sync.Pool{New: func() any { return &Packet{} }}
 func GetPacket() *Packet {
 	p := packetPool.Get().(*Packet)
 	p.PacketNumber = 0
+	p.StreamFrames = nil
 	p.Frames = nil
 	p.LargestAcked = 0
 	p.Length = 0
@@ -51,5 +53,6 @@ func putPacket(p *Packet) {
 		putFrame(f)
 	}
 	p.Frames = nil
+	p.StreamFrames = nil
 	packetPool.Put(p)
 }

internal/ackhandler/sent_packet_handler.go

@@ -243,7 +243,7 @@ func (h *sentPacketHandler) SentPacket(p *Packet) {
 	}
 
 	pnSpace.largestSent = p.PacketNumber
-	isAckEliciting := len(p.Frames) > 0
+	isAckEliciting := len(p.StreamFrames) > 0 || len(p.Frames) > 0
 
 	if isAckEliciting {
 		pnSpace.lastAckElicitingPacketTime = p.SendTime
@@ -424,6 +424,9 @@ func (h *sentPacketHandler) detectAndRemoveAckedPackets(ack *wire.AckFrame, encL
 				f.OnAcked(f.Frame)
 			}
 		}
+		for _, f := range p.StreamFrames {
+			f.Handler.OnAcked(f.Frame)
+		}
 		if err := pnSpace.history.Remove(p.PacketNumber); err != nil {
 			return nil, err
 		}
@@ -790,12 +793,16 @@ func (h *sentPacketHandler) QueueProbePacket(encLevel protocol.EncryptionLevel)
 }
 
 func (h *sentPacketHandler) queueFramesForRetransmission(p *Packet) {
-	if len(p.Frames) == 0 {
+	if len(p.Frames) == 0 && len(p.StreamFrames) == 0 {
 		panic("no frames")
 	}
 	for _, f := range p.Frames {
 		f.OnLost(f.Frame)
 	}
+	for _, f := range p.StreamFrames {
+		f.Handler.OnLost(f.Frame)
+	}
+	p.StreamFrames = nil
 	p.Frames = nil
 }