Reland Use CopyOnWriteBuffer instead of Buffer to avoid unnecessary copies.

webrtc/media/engine/webrtcvideoengine2_unittest.cc

 /*
  *  Copyright (c) 2004 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 2941 matching lines @@
   EXPECT_TRUE(channel_->SetSendParameters(send_parameters_));
 
   const std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs1);
   const std::vector<uint32_t> rtx_ssrcs = MAKE_VECTOR(kRtxSsrcs1);
 
   ASSERT_EQ(0u, fake_call_->GetVideoReceiveStreams().size());
   const size_t kDataLength = 12;
   uint8_t data[kDataLength];
   memset(data, 0, sizeof(data));
   rtc::SetBE32(&data[8], ssrcs[0]);
-  rtc::Buffer packet(data, kDataLength);
+  rtc::CopyOnWriteBuffer packet(data, kDataLength);
   rtc::PacketTime packet_time;
   channel_->OnPacketReceived(&packet, packet_time);
 
   ASSERT_EQ(1u, fake_call_->GetVideoReceiveStreams().size())
       << "No default receive stream created.";
   FakeVideoReceiveStream* recv_stream = fake_call_->GetVideoReceiveStreams()[0];
   EXPECT_EQ(0u, recv_stream->GetConfig().rtp.rtx.size())
       << "Default receive stream should not have configured RTX";
 
   EXPECT_TRUE(channel_->AddRecvStream(
@@ skipping 132 matching lines @@
   recv_parameters_.codecs.push_back(red_rtx_codec);
   EXPECT_TRUE(channel_->SetRecvParameters(recv_parameters_));
 
   ASSERT_EQ(0u, fake_call_->GetVideoReceiveStreams().size());
   const size_t kDataLength = 12;
   uint8_t data[kDataLength];
   memset(data, 0, sizeof(data));
 
   rtc::Set8(data, 1, payload_type);
   rtc::SetBE32(&data[8], kIncomingUnsignalledSsrc);
-  rtc::Buffer packet(data, kDataLength);
+  rtc::CopyOnWriteBuffer packet(data, kDataLength);
   rtc::PacketTime packet_time;
   channel_->OnPacketReceived(&packet, packet_time);
 
   if (expect_created_receive_stream) {
     EXPECT_EQ(1u, fake_call_->GetVideoReceiveStreams().size())
         << "Should have created a receive stream for payload type: "
         << payload_type;
   } else {
     EXPECT_EQ(0u, fake_call_->GetVideoReceiveStreams().size())
         << "Shouldn't have created a receive stream for payload type: "
@@ skipping 268 matching lines @@
 }
 
 // Test that we normalize send codec format size in simulcast.
 TEST_F(WebRtcVideoChannel2SimulcastTest, SetSendCodecsWithOddSizeInSimulcast) {
   cricket::VideoCodec codec(kVp8Codec270p);
   codec.width += 1;
   codec.height += 1;
   VerifySimulcastSettings(codec, 2, 2);
 }
 }  // namespace cricket