Remove the dependency of TransportChannel and TransportChannelImpl.

webrtc/pc/channel.h

Index: webrtc/pc/channel.h
diff --git a/webrtc/pc/channel.h b/webrtc/pc/channel.h
index ff98a2fb2760bcc04d8c396fa7be695b9113eaf1..ccff72090248ffe1234cd0853ad8958de1596ebf 100644
--- a/webrtc/pc/channel.h
+++ b/webrtc/pc/channel.h
@@ -160,8 +160,10 @@ class BaseChannel
   sigslot::signal1<const rtc::SentPacket&> SignalSentPacket;
 
   // Only public for unit tests.  Otherwise, consider private.
-  TransportChannel* transport_channel() const { return transport_channel_; }
-  TransportChannel* rtcp_transport_channel() const {
+  DtlsTransportInternal* transport_channel() const {
+    return transport_channel_;
+  }
+  DtlsTransportInternal* rtcp_transport_channel() const {
     return rtcp_transport_channel_;
   }
 
@@ -201,7 +203,7 @@ class BaseChannel
 
   // This does not update writability or "ready-to-send" state; it just
   // disconnects from the old channel and connects to the new one.
-  void SetTransportChannel_n(bool rtcp, TransportChannel* new_channel);
+  void SetTransportChannel_n(bool rtcp, DtlsTransportInternal* new_channel);
 
   bool was_ever_writable() const { return was_ever_writable_; }
   void set_local_content_direction(MediaContentDirection direction) {
@@ -226,8 +228,8 @@ class BaseChannel
     return transport_controller_->signaling_thread();
   }
 
-  void ConnectToTransportChannel(TransportChannel* tc);
-  void DisconnectFromTransportChannel(TransportChannel* tc);
+  void ConnectToTransportChannel(DtlsTransportInternal* tc);
+  void DisconnectFromTransportChannel(DtlsTransportInternal* tc);
 
   void FlushRtcpMessages_n();
 
@@ -246,10 +248,10 @@ class BaseChannel
                             int flags);
   void OnReadyToSend(rtc::PacketTransportInterface* transport);
 
-  void OnDtlsState(TransportChannel* channel, DtlsTransportState state);
+  void OnDtlsState(DtlsTransportInternal* channel, DtlsTransportState state);
 
   void OnSelectedCandidatePairChanged(
-      TransportChannel* channel,
+      IceTransportInternal* channel,
       CandidatePairInterface* selected_candidate_pair,
       int last_sent_packet_id,
       bool ready_to_send);
@@ -288,7 +290,7 @@ class BaseChannel
   bool SetupDtlsSrtp_n(bool rtcp_channel);
   void MaybeSetupDtlsSrtp_n();
   // Set the DTLS-SRTP cipher policy on this channel as appropriate.
-  bool SetDtlsSrtpCryptoSuites_n(TransportChannel* tc, bool rtcp);
+  bool SetDtlsSrtpCryptoSuites_n(DtlsTransportInternal* tc, bool rtcp);
 
   // Should be called whenever the conditions for
   // IsReadyToReceiveMedia/IsReadyToSendMedia are satisfied (or unsatisfied).
@@ -385,9 +387,9 @@ class BaseChannel
   // channels.
   const bool rtcp_enabled_;
   // TODO(johan): Replace TransportChannel* with rtc::PacketTransportInterface*.
-  TransportChannel* transport_channel_ = nullptr;
+  DtlsTransportInternal* transport_channel_ = nullptr;
   std::vector<std::pair<rtc::Socket::Option, int> > socket_options_;
-  TransportChannel* rtcp_transport_channel_ = nullptr;
+  DtlsTransportInternal* rtcp_transport_channel_ = nullptr;
   std::vector<std::pair<rtc::Socket::Option, int> > rtcp_socket_options_;
   SrtpFilter srtp_filter_;
   RtcpMuxFilter rtcp_mux_filter_;