Minor clean up of unused stuff (#525)

pkg/sfu/downtrack.go

@@ -244,7 +244,6 @@ func (d *DownTrack) Bind(t webrtc.TrackLocalContext) (webrtc.RTPCodecParameters,
 // because a track has been stopped.
 func (d *DownTrack) Unbind(_ webrtc.TrackLocalContext) error {
 	d.bound.Store(false)
-	d.receiver.DeleteDownTrack(d.peerID)
 	return nil
 }
 

pkg/sfu/forwarder.go

@@ -8,7 +8,6 @@ import (
 
 	"github.com/livekit/protocol/logger"
 	"github.com/pion/webrtc/v3"
-	"go.uber.org/atomic"
 
 	"github.com/livekit/livekit-server/pkg/sfu/buffer"
 )
@@ -187,8 +186,6 @@ type Forwarder struct {
 
 	rtpMunger *RTPMunger
 	vp8Munger *VP8Munger
-
-	receivedFirstKeyFrame atomic.Bool
 }
 
 func NewForwarder(codec webrtc.RTPCodecCapability, kind webrtc.RTPCodecType, logger logger.Logger) *Forwarder {
@@ -1202,10 +1199,6 @@ func (f *Forwarder) GetTranslationParams(extPkt *buffer.ExtPacket, layer int32)
 	return nil, ErrUnknownKind
 }
 
-func (f *Forwarder) ReceivedFirstKeyFrame() bool {
-	return f.receivedFirstKeyFrame.Load()
-}
-
 // should be called with lock held
 func (f *Forwarder) getTranslationParamsAudio(extPkt *buffer.ExtPacket) (*TranslationParams, error) {
 	if f.lastSSRC != extPkt.Packet.SSRC {
@@ -1265,7 +1258,6 @@ func (f *Forwarder) getTranslationParamsVideo(extPkt *buffer.ExtPacket, layer in
 				if f.currentLayers.spatial == f.maxLayers.spatial {
 					tp.isSwitchingToMaxLayer = true
 				}
-				f.receivedFirstKeyFrame.Store(true)
 			}
 		}
 	}