Revert of Adding the ability to create an RtpSender without a track.

talk/app/webrtc/rtpsender.cc

Index: talk/app/webrtc/rtpsender.cc
diff --git a/talk/app/webrtc/rtpsender.cc b/talk/app/webrtc/rtpsender.cc
index ea10b7b33f9b4e6ef3f92c8e5eab6124b2ac816b..3a78f4598a8d359a6c34b1a93071250a4a1a8114 100644
--- a/talk/app/webrtc/rtpsender.cc
+++ b/talk/app/webrtc/rtpsender.cc
@@ -29,7 +29,6 @@
 
 #include "talk/app/webrtc/localaudiosource.h"
 #include "talk/app/webrtc/videosourceinterface.h"
-#include "webrtc/base/helpers.h"
 
 namespace webrtc {
 
@@ -60,49 +59,34 @@
 }
 
 AudioRtpSender::AudioRtpSender(AudioTrackInterface* track,
-                               const std::string& stream_id,
-                               AudioProviderInterface* provider,
-                               StatsCollector* stats)
+                               uint32_t ssrc,
+                               AudioProviderInterface* provider)
     : id_(track->id()),
-      stream_id_(stream_id),
+      track_(track),
+      ssrc_(ssrc),
       provider_(provider),
-      stats_(stats),
-      track_(track),
       cached_track_enabled_(track->enabled()),
       sink_adapter_(new LocalAudioSinkAdapter()) {
-  RTC_DCHECK(provider != nullptr);
   track_->RegisterObserver(this);
   track_->AddSink(sink_adapter_.get());
-}
-
-AudioRtpSender::AudioRtpSender(AudioProviderInterface* provider,
-                               StatsCollector* stats)
-    : id_(rtc::CreateRandomUuid()),
-      stream_id_(rtc::CreateRandomUuid()),
-      provider_(provider),
-      stats_(stats),
-      sink_adapter_(new LocalAudioSinkAdapter()) {}
+  Reconfigure();
+}
 
 AudioRtpSender::~AudioRtpSender() {
+  track_->RemoveSink(sink_adapter_.get());
+  track_->UnregisterObserver(this);
   Stop();
 }
 
 void AudioRtpSender::OnChanged() {
-  RTC_DCHECK(!stopped_);
   if (cached_track_enabled_ != track_->enabled()) {
     cached_track_enabled_ = track_->enabled();
-    if (can_send_track()) {
-      SetAudioSend();
-    }
+    Reconfigure();
   }
 }
 
 bool AudioRtpSender::SetTrack(MediaStreamTrackInterface* track) {
-  if (stopped_) {
-    LOG(LS_ERROR) << "SetTrack can't be called on a stopped RtpSender.";
-    return false;
-  }
-  if (track && track->kind() != MediaStreamTrackInterface::kAudioKind) {
+  if (track->kind() != "audio") {
     LOG(LS_ERROR) << "SetTrack called on audio RtpSender with " << track->kind()
                   << " track.";
     return false;
@@ -110,83 +94,36 @@
   AudioTrackInterface* audio_track = static_cast<AudioTrackInterface*>(track);
 
   // Detach from old track.
-  if (track_) {
-    track_->RemoveSink(sink_adapter_.get());
-    track_->UnregisterObserver(this);
-  }
-
-  if (can_send_track() && stats_) {
-    stats_->RemoveLocalAudioTrack(track_.get(), ssrc_);
-  }
+  track_->RemoveSink(sink_adapter_.get());
+  track_->UnregisterObserver(this);
 
   // Attach to new track.
-  bool prev_can_send_track = can_send_track();
   track_ = audio_track;
-  if (track_) {
-    cached_track_enabled_ = track_->enabled();
-    track_->RegisterObserver(this);
-    track_->AddSink(sink_adapter_.get());
-  }
-
-  // Update audio provider.
-  if (can_send_track()) {
-    SetAudioSend();
-    if (stats_) {
-      stats_->AddLocalAudioTrack(track_.get(), ssrc_);
-    }
-  } else if (prev_can_send_track) {
-    cricket::AudioOptions options;
-    provider_->SetAudioSend(ssrc_, false, options, nullptr);
-  }
+  cached_track_enabled_ = track_->enabled();
+  track_->RegisterObserver(this);
+  track_->AddSink(sink_adapter_.get());
+  Reconfigure();
   return true;
-}
-
-void AudioRtpSender::SetSsrc(uint32_t ssrc) {
-  if (stopped_ || ssrc == ssrc_) {
-    return;
-  }
-  // If we are already sending with a particular SSRC, stop sending.
-  if (can_send_track()) {
-    cricket::AudioOptions options;
-    provider_->SetAudioSend(ssrc_, false, options, nullptr);
-    if (stats_) {
-      stats_->RemoveLocalAudioTrack(track_.get(), ssrc_);
-    }
-  }
-  ssrc_ = ssrc;
-  if (can_send_track()) {
-    SetAudioSend();
-    if (stats_) {
-      stats_->AddLocalAudioTrack(track_.get(), ssrc_);
-    }
-  }
 }
 
 void AudioRtpSender::Stop() {
   // TODO(deadbeef): Need to do more here to fully stop sending packets.
-  if (stopped_) {
-    return;
-  }
-  if (track_) {
-    track_->RemoveSink(sink_adapter_.get());
-    track_->UnregisterObserver(this);
-  }
-  if (can_send_track()) {
-    cricket::AudioOptions options;
-    provider_->SetAudioSend(ssrc_, false, options, nullptr);
-    if (stats_) {
-      stats_->RemoveLocalAudioTrack(track_.get(), ssrc_);
-    }
-  }
-  stopped_ = true;
-}
-
-void AudioRtpSender::SetAudioSend() {
-  RTC_DCHECK(!stopped_ && can_send_track());
+  if (!provider_) {
+    return;
+  }
+  cricket::AudioOptions options;
+  provider_->SetAudioSend(ssrc_, false, options, nullptr);
+  provider_ = nullptr;
+}
+
+void AudioRtpSender::Reconfigure() {
+  if (!provider_) {
+    return;
+  }
   cricket::AudioOptions options;
   if (track_->enabled() && track_->GetSource()) {
     // TODO(xians): Remove this static_cast since we should be able to connect
-    // a remote audio track to a peer connection.
+    // a remote audio track to peer connection.
     options = static_cast<LocalAudioSource*>(track_->GetSource())->options();
   }
 
@@ -199,42 +136,35 @@
 }
 
 VideoRtpSender::VideoRtpSender(VideoTrackInterface* track,
-                               const std::string& stream_id,
+                               uint32_t ssrc,
                                VideoProviderInterface* provider)
     : id_(track->id()),
-      stream_id_(stream_id),
+      track_(track),
+      ssrc_(ssrc),
       provider_(provider),
-      track_(track),
       cached_track_enabled_(track->enabled()) {
-  RTC_DCHECK(provider != nullptr);
-  track_->RegisterObserver(this);
-}
-
-VideoRtpSender::VideoRtpSender(VideoProviderInterface* provider)
-    : id_(rtc::CreateRandomUuid()),
-      stream_id_(rtc::CreateRandomUuid()),
-      provider_(provider) {}
+  track_->RegisterObserver(this);
+  VideoSourceInterface* source = track_->GetSource();
+  if (source) {
+    provider_->SetCaptureDevice(ssrc_, source->GetVideoCapturer());
+  }
+  Reconfigure();
+}
 
 VideoRtpSender::~VideoRtpSender() {
+  track_->UnregisterObserver(this);
   Stop();
 }
 
 void VideoRtpSender::OnChanged() {
-  RTC_DCHECK(!stopped_);
   if (cached_track_enabled_ != track_->enabled()) {
     cached_track_enabled_ = track_->enabled();
-    if (can_send_track()) {
-      SetVideoSend();
-    }
+    Reconfigure();
   }
 }
 
 bool VideoRtpSender::SetTrack(MediaStreamTrackInterface* track) {
-  if (stopped_) {
-    LOG(LS_ERROR) << "SetTrack can't be called on a stopped RtpSender.";
-    return false;
-  }
-  if (track && track->kind() != MediaStreamTrackInterface::kVideoKind) {
+  if (track->kind() != "video") {
     LOG(LS_ERROR) << "SetTrack called on video RtpSender with " << track->kind()
                   << " track.";
     return false;
@@ -242,72 +172,30 @@
   VideoTrackInterface* video_track = static_cast<VideoTrackInterface*>(track);
 
   // Detach from old track.
-  if (track_) {
-    track_->UnregisterObserver(this);
-  }
+  track_->UnregisterObserver(this);
 
   // Attach to new track.
-  bool prev_can_send_track = can_send_track();
   track_ = video_track;
-  if (track_) {
-    cached_track_enabled_ = track_->enabled();
-    track_->RegisterObserver(this);
-  }
-
-  // Update video provider.
-  if (can_send_track()) {
-    VideoSourceInterface* source = track_->GetSource();
-    // TODO(deadbeef): If SetTrack is called with a disabled track, and the
-    // previous track was enabled, this could cause a frame from the new track
-    // to slip out. Really, what we need is for SetCaptureDevice and
-    // SetVideoSend
-    // to be combined into one atomic operation, all the way down to
-    // WebRtcVideoSendStream.
-    provider_->SetCaptureDevice(ssrc_,
-                                source ? source->GetVideoCapturer() : nullptr);
-    SetVideoSend();
-  } else if (prev_can_send_track) {
-    provider_->SetCaptureDevice(ssrc_, nullptr);
-    provider_->SetVideoSend(ssrc_, false, nullptr);
-  }
+  cached_track_enabled_ = track_->enabled();
+  track_->RegisterObserver(this);
+  Reconfigure();
   return true;
-}
-
-void VideoRtpSender::SetSsrc(uint32_t ssrc) {
-  if (stopped_ || ssrc == ssrc_) {
-    return;
-  }
-  // If we are already sending with a particular SSRC, stop sending.
-  if (can_send_track()) {
-    provider_->SetCaptureDevice(ssrc_, nullptr);
-    provider_->SetVideoSend(ssrc_, false, nullptr);
-  }
-  ssrc_ = ssrc;
-  if (can_send_track()) {
-    VideoSourceInterface* source = track_->GetSource();
-    provider_->SetCaptureDevice(ssrc_,
-                                source ? source->GetVideoCapturer() : nullptr);
-    SetVideoSend();
-  }
 }
 
 void VideoRtpSender::Stop() {
   // TODO(deadbeef): Need to do more here to fully stop sending packets.
-  if (stopped_) {
-    return;
-  }
-  if (track_) {
-    track_->UnregisterObserver(this);
-  }
-  if (can_send_track()) {
-    provider_->SetCaptureDevice(ssrc_, nullptr);
-    provider_->SetVideoSend(ssrc_, false, nullptr);
-  }
-  stopped_ = true;
-}
-
-void VideoRtpSender::SetVideoSend() {
-  RTC_DCHECK(!stopped_ && can_send_track());
+  if (!provider_) {
+    return;
+  }
+  provider_->SetCaptureDevice(ssrc_, nullptr);
+  provider_->SetVideoSend(ssrc_, false, nullptr);
+  provider_ = nullptr;
+}
+
+void VideoRtpSender::Reconfigure() {
+  if (!provider_) {
+    return;
+  }
   const cricket::VideoOptions* options = nullptr;
   VideoSourceInterface* source = track_->GetSource();
   if (track_->enabled() && source) {