Reland Use CopyOnWriteBuffer instead of Buffer to avoid unnecessary copies.

webrtc/api/webrtcsession.cc

 /*
  *  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 1356 matching lines @@
     return false;
   }
   return true;
 }
 
 sigslot::signal0<>* WebRtcSession::GetOnDestroyedSignal() {
   return &SignalDestroyed;
 }
 
 bool WebRtcSession::SendData(const cricket::SendDataParams& params,
-                             const rtc::Buffer& payload,
+                             const rtc::CopyOnWriteBuffer& payload,
                              cricket::SendDataResult* result) {
   if (!data_channel_) {
     LOG(LS_ERROR) << "SendData called when data_channel_ is NULL.";
     return false;
   }
   return data_channel_->SendData(params, payload, result);
 }
 
 bool WebRtcSession::ConnectDataChannel(DataChannel* webrtc_data_channel) {
   if (!data_channel_) {
@@ skipping 459 matching lines @@
 }
 
 void WebRtcSession::OnDtlsSetupFailure(cricket::BaseChannel*, bool rtcp) {
   SetError(ERROR_TRANSPORT,
            rtcp ? kDtlsSetupFailureRtcp : kDtlsSetupFailureRtp);
 }
 
 void WebRtcSession::OnDataChannelMessageReceived(
     cricket::DataChannel* channel,
     const cricket::ReceiveDataParams& params,
-    const rtc::Buffer& payload) {
+    const rtc::CopyOnWriteBuffer& payload) {
   RTC_DCHECK(data_channel_type_ == cricket::DCT_SCTP);
   if (params.type == cricket::DMT_CONTROL && IsOpenMessage(payload)) {
     // Received OPEN message; parse and signal that a new data channel should
     // be created.
     std::string label;
     InternalDataChannelInit config;
     config.id = params.ssrc;
     if (!ParseDataChannelOpenMessage(payload, &label, &config)) {
       LOG(LS_WARNING) << "Failed to parse the OPEN message for sid "
                       << params.ssrc;
@@ skipping 292 matching lines @@
   }
 }
 
 void WebRtcSession::OnSentPacket_w(cricket::TransportChannel* channel,
                                    const rtc::SentPacket& sent_packet) {
   RTC_DCHECK(worker_thread()->IsCurrent());
   media_controller_->call_w()->OnSentPacket(sent_packet);
 }
 
 }  // namespace webrtc