MediaStream API: Update RTCDataChannel to match the specification

public/platform/WebRTCDataChannelHandler.h

Index: public/platform/WebRTCDataChannelHandler.h
diff --git a/public/platform/WebRTCDataChannelHandler.h b/public/platform/WebRTCDataChannelHandler.h
index 211d8ac96e06b1932d4a5d7d709faabd02cfb17b..65ad01bf2d4ed408c1064aaf899ef57a5cccab52 100644
--- a/public/platform/WebRTCDataChannelHandler.h
+++ b/public/platform/WebRTCDataChannelHandler.h
@@ -39,7 +39,17 @@ public:
     virtual void setClient(WebRTCDataChannelHandlerClient*) = 0;
 
     virtual WebString label() = 0;
-    virtual bool isReliable() = 0;
+
+    // DEPRECATED
+    virtual bool isReliable() { return true; }
+
+    virtual bool ordered() const { return false; }
+    virtual unsigned short maxRetransmitTime() const { return 0; }
+    virtual unsigned short maxRetransmits() const { return 0; }
+    virtual WebString protocol() const { return WebString(); }
+    virtual bool negotiated() const { return true; }
+    virtual unsigned short id() const { return 0; }
+
     virtual unsigned long bufferedAmount() = 0;
     virtual bool sendStringData(const WebString&) = 0;
     virtual bool sendRawData(const char*, size_t) = 0;