Replace NULL with nullptr in all C++ files.

webrtc/modules/video_coding/test/video_rtp_play.cc

 /*
  *  Copyright (c) 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 39 matching lines @@
     output_file = webrtc::test::OutputPath() + "RtpPlay_decoded.yuv";
 
   webrtc::SimulatedClock clock(0);
   webrtc::rtpplayer::VcmPayloadSinkFactory factory(
       output_file, &clock, kConfigProtectionEnabled, kConfigProtectionMethod,
       kConfigRttMs, kConfigRenderDelayMs, kConfigMinPlayoutDelayMs);
   std::unique_ptr<webrtc::rtpplayer::RtpPlayerInterface> rtp_player(
       webrtc::rtpplayer::Create(args.inputFile, &factory, &clock, payload_types,
                                 kConfigLossRate, kConfigRttMs,
                                 kConfigReordering));
-  if (rtp_player.get() == NULL) {
+  if (rtp_player.get() == nullptr) {
     return -1;
   }
 
   int ret = 0;
   while ((ret = rtp_player->NextPacket(clock.TimeInMilliseconds())) == 0) {
     ret = factory.DecodeAndProcessAll(true);
     if (ret < 0 || (kConfigMaxRuntimeMs > -1 &&
                     clock.TimeInMilliseconds() >= kConfigMaxRuntimeMs)) {
       break;
     }
@@ skipping 10 matching lines @@
       printf("Failed\n");
       return -1;
     case 0:
       printf("Timeout\n");
       return -1;
   }
 
   webrtc::Trace::ReturnTrace();
   return 0;
 }