Fix for scenario where m-line is revived after being set to port 0.

talk/app/webrtc/rtpreceiver.cc

Index: talk/app/webrtc/rtpreceiver.cc
diff --git a/talk/app/webrtc/rtpreceiver.cc b/talk/app/webrtc/rtpreceiver.cc
index b88554f0ac4d5f6f1108adf042c7284820914ef4..86268e28eb75ed22d7b369938c482451fee3301d 100644
--- a/talk/app/webrtc/rtpreceiver.cc
+++ b/talk/app/webrtc/rtpreceiver.cc
@@ -85,7 +85,7 @@ VideoRtpReceiver::VideoRtpReceiver(VideoTrackInterface* track,
                                    uint32_t ssrc,
                                    VideoProviderInterface* provider)
     : id_(track->id()), track_(track), ssrc_(ssrc), provider_(provider) {
-  provider_->SetVideoPlayout(ssrc_, true, track_->GetSource()->FrameInput());
+  Reconfigure();
 }
 
 VideoRtpReceiver::~VideoRtpReceiver() {
@@ -103,4 +103,8 @@ void VideoRtpReceiver::Stop() {
   provider_ = nullptr;
 }
 
+void VideoRtpReceiver::Reconfigure() {
+  provider_->SetVideoPlayout(ssrc_, true, track_->GetSource()->FrameInput());
+}
+
 }  // namespace webrtc