Replace NULL with nullptr in all C++ files.

webrtc/voice_engine/channel_manager.cc

 /*
  *  Copyright (c) 2011 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 49 matching lines @@
   return channel_owner;
 }
 
 ChannelOwner ChannelManager::GetChannel(int32_t channel_id) {
   rtc::CritScope crit(&lock_);
 
   for (size_t i = 0; i < channels_.size(); ++i) {
     if (channels_[i].channel()->ChannelId() == channel_id)
       return channels_[i];
   }
-  return ChannelOwner(NULL);
+  return ChannelOwner(nullptr);
 }
 
 void ChannelManager::GetAllChannels(std::vector<ChannelOwner>* channels) {
   rtc::CritScope crit(&lock_);
 
   *channels = channels_;
 }
 
 void ChannelManager::DestroyChannel(int32_t channel_id) {
   assert(channel_id >= 0);
   // Holds a reference to a channel, this is used so that we never delete
   // Channels while holding a lock, but rather when the method returns.
-  ChannelOwner reference(NULL);
+  ChannelOwner reference(nullptr);
   {
     rtc::CritScope crit(&lock_);
     std::vector<ChannelOwner>::iterator to_delete = channels_.end();
     for (auto it = channels_.begin(); it != channels_.end(); ++it) {
       Channel* channel = it->channel();
       // For channels associated with the channel to be deleted, disassociate
       // with that channel.
       channel->DisassociateSendChannel(channel_id);
 
       if (channel->ChannelId() == channel_id) {
@@ skipping 24 matching lines @@
 }
 
 ChannelManager::Iterator::Iterator(ChannelManager* channel_manager)
     : iterator_pos_(0) {
   channel_manager->GetAllChannels(&channels_);
 }
 
 Channel* ChannelManager::Iterator::GetChannel() {
   if (iterator_pos_ < channels_.size())
     return channels_[iterator_pos_].channel();
-  return NULL;
+  return nullptr;
 }
 
 bool ChannelManager::Iterator::IsValid() {
   return iterator_pos_ < channels_.size();
 }
 
 void ChannelManager::Iterator::Increment() {
   ++iterator_pos_;
 }
 
 }  // namespace voe
 }  // namespace webrtc