Revert of Separating SCTP code from BaseChannel/MediaChannel.

webrtc/api/datachannel.h

Index: webrtc/api/datachannel.h
diff --git a/webrtc/api/datachannel.h b/webrtc/api/datachannel.h
index 19f95df44484ae94fa0aa875f8ce3f0c72937993..9208ada5ca64f360ea981e976f4fb963f1b2ce4f 100644
--- a/webrtc/api/datachannel.h
+++ b/webrtc/api/datachannel.h
@@ -144,10 +144,11 @@ class DataChannel : public DataChannelInterface,
   // stream on an existing DataMediaChannel, and we've finished negotiation.
   void OnChannelReady(bool writable);
 
-  // Slots for provider to connect signals to.
-  void OnDataReceived(const cricket::ReceiveDataParams& params,
+  // Sigslots from cricket::DataChannel
+  void OnDataReceived(cricket::DataChannel* channel,
+                      const cricket::ReceiveDataParams& params,
                       const rtc::CopyOnWriteBuffer& payload);
-  void OnStreamClosedRemotely(int sid);
+  void OnStreamClosedRemotely(uint32_t sid);
 
   // The remote peer request that this channel should be closed.
   void RemotePeerRequestClose();