Allow to enable frame copy on a video track

go.mod

@@ -2,7 +2,7 @@ module github.com/pion/mediadevices
 
 go 1.13
 
-replace github.com/pion/webrtc/v3 => github.com/EmrysMyrddin/webrtc/v3 v3.0.30-0.20220301133300-cf76910357bd
+replace github.com/pion/webrtc/v3 => github.com/EmrysMyrddin/webrtc/v3 v3.1.25-0.20220301142221-d92d68ff068f
 
 require (
 	github.com/blackjack/webcam v0.0.0-20200313125108-10ed912a8539

go.sum

@@ -1,5 +1,5 @@
-github.com/EmrysMyrddin/webrtc/v3 v3.0.30-0.20220301133300-cf76910357bd h1:LMu4e+BuBW8N1TnzXXz4bB/O47fQzw0CqfyROgzMSx8=
-github.com/EmrysMyrddin/webrtc/v3 v3.0.30-0.20220301133300-cf76910357bd/go.mod h1:mO/yv7fBN3Lp7YNlnYcTj1jtpvNvssJG+7eh6itZ4xM=
+github.com/EmrysMyrddin/webrtc/v3 v3.1.25-0.20220301142221-d92d68ff068f h1:o7MCxR85nZxyOgjkmjtnXHsmPmchX3AEbWb/Bgpy3aI=
+github.com/EmrysMyrddin/webrtc/v3 v3.1.25-0.20220301142221-d92d68ff068f/go.mod h1:mO/yv7fBN3Lp7YNlnYcTj1jtpvNvssJG+7eh6itZ4xM=
 github.com/blackjack/webcam v0.0.0-20200313125108-10ed912a8539 h1:1aIqYfg9s9RETAJHGfVKZW4ok0b22p4QTwk8MsdRtPs=
 github.com/blackjack/webcam v0.0.0-20200313125108-10ed912a8539/go.mod h1:G0X+rEqYPWSq0dG8OMf8M446MtKytzpPjgS3HbdOJZ4=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

track.go

@@ -295,6 +295,7 @@ func newTrackFromDriver(d driver.Driver, constraints MediaTrackConstraints, sele
 type VideoTrack struct {
 	*baseTrack
 	*video.Broadcaster
+	ShouldCopyFrames bool
 }
 
 // NewVideoTrack constructs a new VideoTrack
@@ -346,7 +347,7 @@ func (track *VideoTrack) Unbind(ctx webrtc.TrackLocalContext) error {
 }
 
 func (track *VideoTrack) newEncodedReader(codecNames ...string) (EncodedReadCloser, *codec.RTPCodec, error) {
-	reader := track.NewReader(false)
+	reader := track.NewReader(track.ShouldCopyFrames)
 	inputProp, err := detectCurrentVideoProp(track.Broadcaster)
 	if err != nil {
 		return nil, nil, err