Correct stats for RTCPeerConnectionStats.dataChannels[Opened/Closed].

webrtc/api/datachannel.h

Index: webrtc/api/datachannel.h
diff --git a/webrtc/api/datachannel.h b/webrtc/api/datachannel.h
index 7d7f6c75df7a4fbe65c37b65b71a86e71e007c4f..9208ada5ca64f360ea981e976f4fb963f1b2ce4f 100644
--- a/webrtc/api/datachannel.h
+++ b/webrtc/api/datachannel.h
@@ -180,6 +180,8 @@ class DataChannel : public DataChannelInterface,
     return data_channel_type_;
   }
 
+  // Emitted when state transitions to kOpen.
+  sigslot::signal1<DataChannel*> SignalOpened;
   // Emitted when state transitions to kClosed.
   // In the case of SCTP channels, this signal can be used to tell when the
   // channel's sid is free.