Add PeerConnection IsClosed check.

webrtc/api/peerconnection.cc

Index: webrtc/api/peerconnection.cc
diff --git a/webrtc/api/peerconnection.cc b/webrtc/api/peerconnection.cc
index 5f8acca5669c0c1aabb8a568e9d8a4d46a5c22f9..7acdee6925333608d8e798043dd1d2bd0ae2347a 100644
--- a/webrtc/api/peerconnection.cc
+++ b/webrtc/api/peerconnection.cc
@@ -590,6 +590,9 @@ bool PeerConnection::Initialize(
       new WebRtcSession(media_controller_.get(), factory_->network_thread(),
                         factory_->worker_thread(), factory_->signaling_thread(),
                         port_allocator_.get()));
+
+  session_->SetTransportController(
+      factory_->CreateTransportController(port_allocator_.get()));
   stats_.reset(new StatsCollector(this));
 
   // Initialize the WebRtcSession. It creates transport channels etc.
@@ -760,6 +763,9 @@ bool PeerConnection::RemoveTrack(RtpSenderInterface* sender) {
 rtc::scoped_refptr<DtmfSenderInterface> PeerConnection::CreateDtmfSender(
     AudioTrackInterface* track) {
   TRACE_EVENT0("webrtc", "PeerConnection::CreateDtmfSender");
+  if (IsClosed()) {
+    return nullptr;
+  }
   if (!track) {
     LOG(LS_ERROR) << "CreateDtmfSender - track is NULL.";
     return NULL;
@@ -782,6 +788,9 @@ rtc::scoped_refptr<RtpSenderInterface> PeerConnection::CreateSender(
     const std::string& kind,
     const std::string& stream_id) {
   TRACE_EVENT0("webrtc", "PeerConnection::CreateSender");
+  if (IsClosed()) {
+    return nullptr;
+  }
   rtc::scoped_refptr<RtpSenderInterface> new_sender;
   if (kind == MediaStreamTrackInterface::kAudioKind) {
     new_sender = RtpSenderProxy::Create(
@@ -984,6 +993,9 @@ void PeerConnection::SetLocalDescription(
     SetSessionDescriptionObserver* observer,
     SessionDescriptionInterface* desc) {
   TRACE_EVENT0("webrtc", "PeerConnection::SetLocalDescription");
+  if (IsClosed()) {
+    return;
+  }
   if (!VERIFY(observer != nullptr)) {
     LOG(LS_ERROR) << "SetLocalDescription - observer is NULL.";
     return;
@@ -1062,6 +1074,9 @@ void PeerConnection::SetRemoteDescription(
     SetSessionDescriptionObserver* observer,
     SessionDescriptionInterface* desc) {
   TRACE_EVENT0("webrtc", "PeerConnection::SetRemoteDescription");
+  if (IsClosed()) {
+    return;
+  }
   if (!VERIFY(observer != nullptr)) {
     LOG(LS_ERROR) << "SetRemoteDescription - observer is NULL.";
     return;
@@ -1182,6 +1197,9 @@ bool PeerConnection::SetConfiguration(const RTCConfiguration& configuration) {
 bool PeerConnection::AddIceCandidate(
     const IceCandidateInterface* ice_candidate) {
   TRACE_EVENT0("webrtc", "PeerConnection::AddIceCandidate");
+  if (IsClosed()) {
+    return false;
+  }
   return session_->ProcessIceMessage(ice_candidate);
 }
 
@@ -1226,7 +1244,6 @@ void PeerConnection::Close() {
   // Update stats here so that we have the most recent stats for tracks and
   // streams before the channels are closed.
   stats_->UpdateStats(kStatsOutputLevelStandard);
-
   session_->Close();
 }
 
@@ -1367,17 +1384,26 @@ void PeerConnection::OnIceGatheringChange(
 
 void PeerConnection::OnIceCandidate(const IceCandidateInterface* candidate) {
   RTC_DCHECK(signaling_thread()->IsCurrent());
+  if (IsClosed()) {
+    return;
+  }
   observer_->OnIceCandidate(candidate);
 }
 
 void PeerConnection::OnIceCandidatesRemoved(
     const std::vector<cricket::Candidate>& candidates) {
   RTC_DCHECK(signaling_thread()->IsCurrent());
+  if (IsClosed()) {
+    return;
+  }
   observer_->OnIceCandidatesRemoved(candidates);
 }
 
 void PeerConnection::OnIceConnectionReceivingChange(bool receiving) {
   RTC_DCHECK(signaling_thread()->IsCurrent());
+  if (IsClosed()) {
+    return;
+  }
   observer_->OnIceConnectionReceivingChange(receiving);
 }
 
@@ -1397,6 +1423,9 @@ void PeerConnection::ChangeSignalingState(
 
 void PeerConnection::OnAudioTrackAdded(AudioTrackInterface* track,
                                        MediaStreamInterface* stream) {
+  if (IsClosed()) {
+    return;
+  }
   auto sender = FindSenderForTrack(track);
   if (sender != senders_.end()) {
     // We already have a sender for this track, so just change the stream_id
@@ -1427,6 +1456,9 @@ void PeerConnection::OnAudioTrackAdded(AudioTrackInterface* track,
 // indefinitely, when we have unified plan SDP.
 void PeerConnection::OnAudioTrackRemoved(AudioTrackInterface* track,
                                          MediaStreamInterface* stream) {
+  if (IsClosed()) {
+    return;
+  }
   auto sender = FindSenderForTrack(track);
   if (sender == senders_.end()) {
     LOG(LS_WARNING) << "RtpSender for track with id " << track->id()
@@ -1439,6 +1471,9 @@ void PeerConnection::OnAudioTrackRemoved(AudioTrackInterface* track,
 
 void PeerConnection::OnVideoTrackAdded(VideoTrackInterface* track,
                                        MediaStreamInterface* stream) {
+  if (IsClosed()) {
+    return;
+  }
   auto sender = FindSenderForTrack(track);
   if (sender != senders_.end()) {
     // We already have a sender for this track, so just change the stream_id
@@ -1461,6 +1496,9 @@ void PeerConnection::OnVideoTrackAdded(VideoTrackInterface* track,
 
 void PeerConnection::OnVideoTrackRemoved(VideoTrackInterface* track,
                                          MediaStreamInterface* stream) {
+  if (IsClosed()) {
+    return;
+  }
   auto sender = FindSenderForTrack(track);
   if (sender == senders_.end()) {
     LOG(LS_WARNING) << "RtpSender for track with id " << track->id()