rtc_stats: Update code to remove chromium style warnings suppression.

webrtc/api/stats/rtcstats_objects.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.
  */
 
 #ifndef WEBRTC_API_STATS_RTCSTATS_OBJECTS_H_
 #define WEBRTC_API_STATS_RTCSTATS_OBJECTS_H_
 
 #include <string>
 
 #include "webrtc/api/stats/rtcstats.h"
 
 namespace webrtc {
 
 class RTCPeerConnectionStats : public RTCStats {
  public:
   RTCPeerConnectionStats(const std::string& id, int64_t timestamp_us);
   RTCPeerConnectionStats(std::string&& id, int64_t timestamp_us);
+  RTCPeerConnectionStats(const RTCPeerConnectionStats& other);
+  ~RTCPeerConnectionStats() override;
 
-  WEBRTC_RTCSTATS_IMPL(RTCStats, RTCPeerConnectionStats,
-      &data_channels_opened,
-      &data_channels_closed);
+  WEBRTC_RTCSTATS_DECL();
 
   RTCStatsMember<uint32_t> data_channels_opened;
   RTCStatsMember<uint32_t> data_channels_closed;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_API_STATS_RTCSTATS_OBJECTS_H_