Fixing scenario where track is rejected and later un-rejected.

talk/app/webrtc/mediastreamhandler.cc

Index: talk/app/webrtc/mediastreamhandler.cc
diff --git a/talk/app/webrtc/mediastreamhandler.cc b/talk/app/webrtc/mediastreamhandler.cc
index f68699d6298c40bc6c6e111035ad6abc362652df..08be35ec865e080bccffc76368f934aa7f343035 100644
--- a/talk/app/webrtc/mediastreamhandler.cc
+++ b/talk/app/webrtc/mediastreamhandler.cc
@@ -90,7 +90,7 @@ LocalAudioTrackHandler::LocalAudioTrackHandler(
       audio_track_(track),
       provider_(provider),
       sink_adapter_(new LocalAudioSinkAdapter()) {
-  OnEnabledChanged();
+  Start();
   track->AddSink(sink_adapter_.get());
 }
 
@@ -101,6 +101,10 @@ void LocalAudioTrackHandler::OnStateChanged() {
   // TODO(perkj): What should happen when the state change?
 }
 
+void LocalAudioTrackHandler::Start() {
+  OnEnabledChanged();
+}
+
 void LocalAudioTrackHandler::Stop() {
   audio_track_->RemoveSink(sink_adapter_.get());
   cricket::AudioOptions options;
@@ -132,13 +136,19 @@ RemoteAudioTrackHandler::RemoteAudioTrackHandler(
       audio_track_(track),
       provider_(provider) {
   track->GetSource()->RegisterAudioObserver(this);
-  OnEnabledChanged();
+  Start();
 }
 
 RemoteAudioTrackHandler::~RemoteAudioTrackHandler() {
   audio_track_->GetSource()->UnregisterAudioObserver(this);
 }
 
+void RemoteAudioTrackHandler::Start() {
+  // TODO(deadbeef) - Should we remember the audio playout volume last set,
+  // and set it again in case the audio channel was destroyed and recreated?
+  OnEnabledChanged();
+}
+
 void RemoteAudioTrackHandler::Stop() {
   provider_->SetAudioPlayout(ssrc(), false, NULL);
 }
@@ -166,10 +176,7 @@ LocalVideoTrackHandler::LocalVideoTrackHandler(
     : TrackHandler(track, ssrc),
       local_video_track_(track),
       provider_(provider) {
-  VideoSourceInterface* source = local_video_track_->GetSource();
-  if (source)
-    provider_->SetCaptureDevice(ssrc, source->GetVideoCapturer());
-  OnEnabledChanged();
+  Start();
 }
 
 LocalVideoTrackHandler::~LocalVideoTrackHandler() {
@@ -178,6 +185,13 @@ LocalVideoTrackHandler::~LocalVideoTrackHandler() {
 void LocalVideoTrackHandler::OnStateChanged() {
 }
 
+void LocalVideoTrackHandler::Start() {
+  VideoSourceInterface* source = local_video_track_->GetSource();
+  if (source)
+    provider_->SetCaptureDevice(ssrc(), source->GetVideoCapturer());
+  OnEnabledChanged();
+}
+
 void LocalVideoTrackHandler::Stop() {
   provider_->SetCaptureDevice(ssrc(), NULL);
   provider_->SetVideoSend(ssrc(), false, NULL);
@@ -199,14 +213,18 @@ RemoteVideoTrackHandler::RemoteVideoTrackHandler(
     : TrackHandler(track, ssrc),
       remote_video_track_(track),
       provider_(provider) {
-  OnEnabledChanged();
-  provider_->SetVideoPlayout(ssrc, true,
-                             remote_video_track_->GetSource()->FrameInput());
+  Start();
 }
 
 RemoteVideoTrackHandler::~RemoteVideoTrackHandler() {
 }
 
+void RemoteVideoTrackHandler::Start() {
+  OnEnabledChanged();
+  provider_->SetVideoPlayout(ssrc(), true,
+                             remote_video_track_->GetSource()->FrameInput());
+}
+
 void RemoteVideoTrackHandler::Stop() {
   // Since cricket::VideoRenderer is not reference counted
   // we need to remove the renderer before we are deleted.
@@ -301,6 +319,12 @@ void LocalMediaStreamHandler::AddVideoTrack(VideoTrackInterface* video_track,
   track_handlers_.push_back(handler);
 }
 
+void LocalMediaStreamHandler::RestartAllTracks() {
+  for (auto it : track_handlers_) {
+    it->Start();
+  }
+}
+
 RemoteMediaStreamHandler::RemoteMediaStreamHandler(
     MediaStreamInterface* stream,
     AudioProviderInterface* audio_provider,
@@ -327,6 +351,12 @@ void RemoteMediaStreamHandler::AddVideoTrack(VideoTrackInterface* video_track,
   track_handlers_.push_back(handler);
 }
 
+void RemoteMediaStreamHandler::RestartAllTracks() {
+  for (auto it : track_handlers_) {
+    it->Start();
+  }
+}
+
 MediaStreamHandlerContainer::MediaStreamHandlerContainer(
     AudioProviderInterface* audio_provider,
     VideoProviderInterface* video_provider)
@@ -396,6 +426,12 @@ void MediaStreamHandlerContainer::RemoveRemoteTrack(
   handler->RemoveTrack(track);
 }
 
+void MediaStreamHandlerContainer::RestartAllRemoteTracks() {
+  for (auto it : remote_streams_handlers_) {
+    it->RestartAllTracks();
+  }
+}
+
 void MediaStreamHandlerContainer::RemoveLocalStream(
     MediaStreamInterface* stream) {
   DeleteStreamHandler(&local_streams_handlers_, stream);
@@ -438,6 +474,12 @@ void MediaStreamHandlerContainer::RemoveLocalTrack(
   handler->RemoveTrack(track);
 }
 
+void MediaStreamHandlerContainer::RestartAllLocalTracks() {
+  for (auto it : local_streams_handlers_) {
+    it->RestartAllTracks();
+  }
+}
+
 MediaStreamHandler* MediaStreamHandlerContainer::CreateRemoteStreamHandler(
     MediaStreamInterface* stream) {
   ASSERT(!FindStreamHandler(remote_streams_handlers_, stream));