Replace NULL with nullptr in all C++ files.

webrtc/modules/rtp_rtcp/source/nack_rtx_unittest.cc

 /*
 *  Copyright (c) 2013 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 @@
 
 class RtxLoopBackTransport : public webrtc::Transport {
  public:
   explicit RtxLoopBackTransport(uint32_t rtx_ssrc)
       : count_(0),
         packet_loss_(0),
         consecutive_drop_start_(0),
         consecutive_drop_end_(0),
         rtx_ssrc_(rtx_ssrc),
         count_rtx_ssrc_(0),
-        rtp_payload_registry_(NULL),
-        rtp_receiver_(NULL),
-        module_(NULL) {}
+        rtp_payload_registry_(nullptr),
+        rtp_receiver_(nullptr),
+        module_(nullptr) {}
 
   void SetSendModule(RtpRtcp* rtpRtcpModule,
                      RTPPayloadRegistry* rtp_payload_registry,
                      RtpReceiver* receiver) {
     module_ = rtpRtcpModule;
     rtp_payload_registry_ = rtp_payload_registry;
     rtp_receiver_ = receiver;
   }
 
   void DropEveryNthPacket(int n) { packet_loss_ = n; }
@@ skipping 243 matching lines @@
   RunRtxTest(kRtxRetransmitted, 10);
   EXPECT_EQ(kTestSequenceNumber, *(receiver_.sequence_numbers_.begin()));
   EXPECT_EQ(kTestSequenceNumber + kTestNumberOfPackets - 1,
             *(receiver_.sequence_numbers_.rbegin()));
   EXPECT_EQ(kTestNumberOfPackets, receiver_.sequence_numbers_.size());
   EXPECT_EQ(kTestNumberOfRtxPackets, transport_.count_rtx_ssrc_);
   EXPECT_TRUE(ExpectedPacketsReceived());
 }
 
 }  // namespace webrtc