Use VoiceChannel/VideoChannel directly from RtpSender/RtpReceiver.

This eliminates the need for the extra layer of indirection provided by
mediastreamprovider.h. It will thus make it easier to implement new
functionality in RtpSender/RtpReceiver.

It also brings us one step closer to the end goal of combining "senders"
and "send streams". Currently the sender still needs to go through the
BaseChannel and MediaChannel, using an SSRC as a key.

R=pthatcher@webrtc.org

Review URL: https://codereview.webrtc.org/2046173002 .

Cr-Commit-Position: refs/heads/master@{#13285}

webrtc/api/rtpreceiver.h

@@ -10,20 +10,21 @@
 
 // This file contains classes that implement RtpReceiverInterface.
 // An RtpReceiver associates a MediaStreamTrackInterface with an underlying
-// transport (provided by AudioProviderInterface/VideoProviderInterface)
+// transport (provided by cricket::VoiceChannel/cricket::VideoChannel)
 
 #ifndef WEBRTC_API_RTPRECEIVER_H_
 #define WEBRTC_API_RTPRECEIVER_H_
 
 #include <string>
 
-#include "webrtc/api/mediastreamprovider.h"
+#include "webrtc/api/mediastreaminterface.h"
 #include "webrtc/api/rtpreceiverinterface.h"
 #include "webrtc/api/remoteaudiosource.h"
 #include "webrtc/api/videotracksource.h"
 #include "webrtc/base/basictypes.h"
 #include "webrtc/base/sigslot.h"
 #include "webrtc/media/base/videobroadcaster.h"
+#include "webrtc/pc/channel.h"
 
 namespace webrtc {
 
@@ -41,7 +42,7 @@ class AudioRtpReceiver : public ObserverInterface,
   AudioRtpReceiver(MediaStreamInterface* stream,
                    const std::string& track_id,
                    uint32_t ssrc,
-                   AudioProviderInterface* provider);
+                   cricket::VoiceChannel* channel);
 
   virtual ~AudioRtpReceiver();
 
@@ -60,6 +61,10 @@ class AudioRtpReceiver : public ObserverInterface,
     return track_.get();
   }
 
+  cricket::MediaType media_type() const override {
+    return cricket::MEDIA_TYPE_AUDIO;
+  }
+
   std::string id() const override { return id_; }
 
   RtpParameters GetParameters() const override;
@@ -70,17 +75,21 @@ class AudioRtpReceiver : public ObserverInterface,
 
   void SetObserver(RtpReceiverObserverInterface* observer) override;
 
-  cricket::MediaType media_type() override { return cricket::MEDIA_TYPE_AUDIO; }
+  // Does not take ownership.
+  // Should call SetChannel(nullptr) before |channel| is destroyed.
+  void SetChannel(cricket::VoiceChannel* channel);
 
  private:
   void Reconfigure();
-  void OnFirstAudioPacketReceived();
+  void OnFirstPacketReceived(cricket::BaseChannel* channel);
 
   const std::string id_;
   const uint32_t ssrc_;
-  AudioProviderInterface* provider_;  // Set to null in Stop().
+  cricket::VoiceChannel* channel_;
   const rtc::scoped_refptr<AudioTrackInterface> track_;
   bool cached_track_enabled_;
+  double cached_volume_ = 1;
+  bool stopped_ = false;
   RtpReceiverObserverInterface* observer_ = nullptr;
   bool received_first_packet_ = false;
 };
@@ -92,7 +101,7 @@ class VideoRtpReceiver : public rtc::RefCountedObject<RtpReceiverInternal>,
                    const std::string& track_id,
                    rtc::Thread* worker_thread,
                    uint32_t ssrc,
-                   VideoProviderInterface* provider);
+                   cricket::VideoChannel* channel);
 
   virtual ~VideoRtpReceiver();
 
@@ -105,6 +114,10 @@ class VideoRtpReceiver : public rtc::RefCountedObject<RtpReceiverInternal>,
     return track_.get();
   }
 
+  cricket::MediaType media_type() const override {
+    return cricket::MEDIA_TYPE_VIDEO;
+  }
+
   std::string id() const override { return id_; }
 
   RtpParameters GetParameters() const override;
@@ -115,14 +128,16 @@ class VideoRtpReceiver : public rtc::RefCountedObject<RtpReceiverInternal>,
 
   void SetObserver(RtpReceiverObserverInterface* observer) override;
 
-  cricket::MediaType media_type() override { return cricket::MEDIA_TYPE_VIDEO; }
+  // Does not take ownership.
+  // Should call SetChannel(nullptr) before |channel| is destroyed.
+  void SetChannel(cricket::VideoChannel* channel);
 
  private:
-  void OnFirstVideoPacketReceived();
+  void OnFirstPacketReceived(cricket::BaseChannel* channel);
 
   std::string id_;
   uint32_t ssrc_;
-  VideoProviderInterface* provider_;
+  cricket::VideoChannel* channel_;
   // |broadcaster_| is needed since the decoder can only handle one sink.
   // It might be better if the decoder can handle multiple sinks and consider
   // the VideoSinkWants.
@@ -131,6 +146,7 @@ class VideoRtpReceiver : public rtc::RefCountedObject<RtpReceiverInternal>,
   // the VideoRtpReceiver is stopped.
   rtc::scoped_refptr<VideoTrackSource> source_;
   rtc::scoped_refptr<VideoTrackInterface> track_;
+  bool stopped_ = false;
   RtpReceiverObserverInterface* observer_ = nullptr;
   bool received_first_packet_ = false;
 };