Replace NULL with nullptr in all C++ files.

webrtc/modules/audio_processing/transient/click_annotate.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 64 matching lines @@
   size_t file_samples_read = ReadInt16FromFileToFloatBuffer(
       pcm_file.get(),
       audio_buffer_length,
       audio_buffer.get());
   for (int time = 0; file_samples_read > 0; time += chunk_size_ms) {
     // Pad the rest of the buffer with zeros.
     for (size_t i = file_samples_read; i < audio_buffer_length; ++i) {
       audio_buffer[i] = 0.0;
     }
     float value =
-        detector.Detect(audio_buffer.get(), audio_buffer_length, NULL, 0);
+        detector.Detect(audio_buffer.get(), audio_buffer_length, nullptr, 0);
     if (value < 0.5f) {
       value = time;
     } else {
       value = FLT_MAX;
       ++lost_packets;
     }
     send_times.push_back(value);
 
     // Read next buffer from the PCM test file.
     file_samples_read = ReadInt16FromFileToFloatBuffer(pcm_file.get(),
                                                        audio_buffer_length,
                                                        audio_buffer.get());
   }
 
   size_t floats_written = WriteFloatBufferToFile(dat_file.get(),
                                                  send_times.size(),
                                                  &send_times[0]);
 
   if (floats_written == 0) {
     printf("\nThe send times could not be written to DAT file\n\n");
     return -1;
   }
 
   pcm_file->CloseFile();
   dat_file->CloseFile();
 
   return lost_packets;
 }