Mark template class RefCountedObject as final.

pc/quicdatachannel.h

 /*
  *  Copyright 2016 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 57 matching lines @@
 // - The remote QuicSession creates a ReliableQuicStream to receive the data.
 //   The remote QuicDataTransport dispatches the ReliableQuicStream to the
 //   QuicDataChannel with the same id as this data channel.
 //
 // - The remote QuicDataChannel queues data from the ReliableQuicStream. Once
 //   it receives a QUIC stream frame with a FIN, it provides the message to the
 //   DataChannelObserver.
 //
 // TODO(mikescarlett): Implement ordered delivery, unreliable delivery, and
 // an OPEN message similar to the one for SCTP.
-class QuicDataChannel : public rtc::RefCountedObject<DataChannelInterface>,
+class QuicDataChannel : public DataChannelInterface,
                         public sigslot::has_slots<> {
  public:
   // Message stores buffered data from the incoming QUIC stream. The QUIC stream
   // is provided so that remaining data can be received from the remote peer.
   struct Message {
     uint64_t id;
     rtc::CopyOnWriteBuffer buffer;
     cricket::ReliableQuicStream* stream;
   };
 
@@ skipping 122 matching lines @@
   uint64_t next_message_id_;
 
   // Variables for application use.
   const std::string& label_;
   const std::string& protocol_;
 };
 
 }  // namespace webrtc
 
 #endif  // PC_QUICDATACHANNEL_H_