DataChannelInterface: Remove default implementation of methods.

webrtc/api/datachannelinterface.h

 /*
  *  Copyright 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 107 matching lines @@
   // implemented these APIs. They should all just return the values the
   // DataChannel was created with.
   virtual bool ordered() const { return false; }
   virtual uint16_t maxRetransmitTime() const { return 0; }
   virtual uint16_t maxRetransmits() const { return 0; }
   virtual std::string protocol() const { return std::string(); }
   virtual bool negotiated() const { return false; }
 
   virtual int id() const = 0;
   virtual DataState state() const = 0;
-  // TODO(hbos): Default implementations of [messages/bytes]_[sent/received] as
-  // to not break Chromium. Fix Chromium's implementation as soon as this rolls.
-  // crbug.com/654927
-  virtual uint32_t messages_sent() const { return 0; }
-  virtual uint64_t bytes_sent() const { return 0; }
-  virtual uint32_t messages_received() const { return 0; }
-  virtual uint64_t bytes_received() const { return 0; }
+  virtual uint32_t messages_sent() const = 0;
+  virtual uint64_t bytes_sent() const = 0;
+  virtual uint32_t messages_received() const = 0;
+  virtual uint64_t bytes_received() const = 0;
   // The buffered_amount returns the number of bytes of application data
   // (UTF-8 text and binary data) that have been queued using SendBuffer but
   // have not yet been transmitted to the network.
   virtual uint64_t buffered_amount() const = 0;
   virtual void Close() = 0;
   // Sends |data| to the remote peer.
   virtual bool Send(const DataBuffer& buffer) = 0;
 
  protected:
   virtual ~DataChannelInterface() {}
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_API_DATACHANNELINTERFACE_H_