Replace NULL with nullptr in all C++ files.

webrtc/test/call_test.cc

 /*
  *  Copyright (c) 2014 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 128 matching lines @@
     video_send_stream_->Start();
   for (VideoReceiveStream* video_recv_stream : video_receive_streams_)
     video_recv_stream->Start();
   if (audio_send_stream_) {
     audio_send_stream_->Start();
   }
   for (AudioReceiveStream* audio_recv_stream : audio_receive_streams_)
     audio_recv_stream->Start();
   for (FlexfecReceiveStream* flexfec_recv_stream : flexfec_receive_streams_)
     flexfec_recv_stream->Start();
-  if (frame_generator_capturer_.get() != NULL)
+  if (frame_generator_capturer_.get() != nullptr)
     frame_generator_capturer_->Start();
 }
 
 void CallTest::Stop() {
-  if (frame_generator_capturer_.get() != NULL)
+  if (frame_generator_capturer_.get() != nullptr)
     frame_generator_capturer_->Stop();
   for (FlexfecReceiveStream* flexfec_recv_stream : flexfec_receive_streams_)
     flexfec_recv_stream->Stop();
   for (AudioReceiveStream* audio_recv_stream : audio_receive_streams_)
     audio_recv_stream->Stop();
   if (audio_send_stream_) {
     audio_send_stream_->Stop();
   }
   for (VideoReceiveStream* video_recv_stream : video_receive_streams_)
     video_recv_stream->Stop();
@@ skipping 330 matching lines @@
 
 EndToEndTest::EndToEndTest(unsigned int timeout_ms) : BaseTest(timeout_ms) {
 }
 
 bool EndToEndTest::ShouldCreateReceivers() const {
   return true;
 }
 
 }  // namespace test
 }  // namespace webrtc