Replace NULL with nullptr in all C++ files.

webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc

Index: webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc
diff --git a/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc b/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc
index af91c69f694d7cd112a536d4e0260fe022436d57..e64ad932567615a0d9615f3925049e97e4fcaa8e 100644
--- a/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc
+++ b/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc
@@ -107,7 +107,7 @@ AudioConferenceMixer* AudioConferenceMixer::Create(int id) {
     AudioConferenceMixerImpl* mixer = new AudioConferenceMixerImpl(id);
     if(!mixer->Init()) {
         delete mixer;
-        return NULL;
+        return nullptr;
     }
     return mixer;
 }
@@ -115,10 +115,10 @@ AudioConferenceMixer* AudioConferenceMixer::Create(int id) {
 AudioConferenceMixerImpl::AudioConferenceMixerImpl(int id)
     : _id(id),
       _minimumMixingFreq(kLowestPossible),
-      _mixReceiver(NULL),
+      _mixReceiver(nullptr),
       _outputFrequency(kDefaultFrequency),
       _sampleSize(0),
-      _audioFramePool(NULL),
+      _audioFramePool(nullptr),
       _participantList(),
       _additionalParticipantList(),
       _numMixedParticipants(0),
@@ -129,12 +129,12 @@ AudioConferenceMixerImpl::AudioConferenceMixerImpl(int id)
 
 bool AudioConferenceMixerImpl::Init() {
     _crit.reset(CriticalSectionWrapper::CreateCriticalSection());
-    if (_crit.get() == NULL)
-        return false;
+    if (_crit.get() == nullptr)
+      return false;
 
     _cbCrit.reset(CriticalSectionWrapper::CreateCriticalSection());
-    if(_cbCrit.get() == NULL)
-        return false;
+    if (_cbCrit.get() == nullptr)
+      return false;
 
     Config config;
     config.Set<ExperimentalAgc>(new ExperimentalAgc(false));
@@ -144,8 +144,8 @@ bool AudioConferenceMixerImpl::Init() {
 
     MemoryPool<AudioFrame>::CreateMemoryPool(_audioFramePool,
                                              DEFAULT_AUDIO_FRAME_POOLSIZE);
-    if(_audioFramePool == NULL)
-        return false;
+    if (_audioFramePool == nullptr)
+      return false;
 
     if(SetOutputFrequency(kDefaultFrequency) == -1)
         return false;
@@ -175,7 +175,7 @@ bool AudioConferenceMixerImpl::Init() {
 
 AudioConferenceMixerImpl::~AudioConferenceMixerImpl() {
     MemoryPool<AudioFrame>::DeleteMemoryPool(_audioFramePool);
-    assert(_audioFramePool == NULL);
+    assert(_audioFramePool == nullptr);
 }
 
 // Process should be called every kProcessPeriodicityInMs ms
@@ -265,7 +265,7 @@ void AudioConferenceMixerImpl::Process() {
     }
 
     // Get an AudioFrame for mixing from the memory pool.
-    AudioFrame* mixedAudio = NULL;
+    AudioFrame* mixedAudio = nullptr;
     if(_audioFramePool->PopMemory(mixedAudio) == -1) {
         WEBRTC_TRACE(kTraceMemory, kTraceAudioMixerServer, _id,
                      "failed PopMemory() call");
@@ -284,7 +284,7 @@ void AudioConferenceMixerImpl::Process() {
             std::max(MaxNumChannels(&additionalFramesList),
                      MaxNumChannels(&rampOutList)));
 
-        mixedAudio->UpdateFrame(-1, _timeStamp, NULL, 0, _outputFrequency,
+        mixedAudio->UpdateFrame(-1, _timeStamp, nullptr, 0, _outputFrequency,
                                 AudioFrame::kNormalSpeech,
                                 AudioFrame::kVadPassive, num_mixed_channels);
 
@@ -312,13 +312,9 @@ void AudioConferenceMixerImpl::Process() {
 
     {
         CriticalSectionScoped cs(_cbCrit.get());
-        if(_mixReceiver != NULL) {
-            const AudioFrame** dummy = NULL;
-            _mixReceiver->NewMixedAudio(
-                _id,
-                *mixedAudio,
-                dummy,
-                0);
+        if (_mixReceiver != nullptr) {
+          const AudioFrame** dummy = nullptr;
+          _mixReceiver->NewMixedAudio(_id, *mixedAudio, dummy, 0);
         }
     }
 
@@ -337,8 +333,8 @@ void AudioConferenceMixerImpl::Process() {
 int32_t AudioConferenceMixerImpl::RegisterMixedStreamCallback(
     AudioMixerOutputReceiver* mixReceiver) {
     CriticalSectionScoped cs(_cbCrit.get());
-    if(_mixReceiver != NULL) {
-        return -1;
+    if (_mixReceiver != nullptr) {
+      return -1;
     }
     _mixReceiver = mixReceiver;
     return 0;
@@ -346,10 +342,10 @@ int32_t AudioConferenceMixerImpl::RegisterMixedStreamCallback(
 
 int32_t AudioConferenceMixerImpl::UnRegisterMixedStreamCallback() {
     CriticalSectionScoped cs(_cbCrit.get());
-    if(_mixReceiver == NULL) {
-        return -1;
+    if (_mixReceiver == nullptr) {
+      return -1;
     }
-    _mixReceiver = NULL;
+    _mixReceiver = nullptr;
     return 0;
 }
 
@@ -546,7 +542,7 @@ void AudioConferenceMixerImpl::UpdateToMix(
 
         bool wasMixed = false;
         wasMixed = (*participant)->_mixHistory->WasMixed();
-        AudioFrame* audioFrame = NULL;
+        AudioFrame* audioFrame = nullptr;
         if(_audioFramePool->PopMemory(audioFrame) == -1) {
             WEBRTC_TRACE(kTraceMemory, kTraceAudioMixerServer, _id,
                          "failed PopMemory() call");
@@ -734,12 +730,12 @@ void AudioConferenceMixerImpl::GetAdditionalAudio(
              additionalParticipantList.begin();
          participant != additionalParticipantList.end();
          ++participant) {
-        AudioFrame* audioFrame = NULL;
-        if(_audioFramePool->PopMemory(audioFrame) == -1) {
-            WEBRTC_TRACE(kTraceMemory, kTraceAudioMixerServer, _id,
-                         "failed PopMemory() call");
-            assert(false);
-            return;
+      AudioFrame* audioFrame = nullptr;
+      if (_audioFramePool->PopMemory(audioFrame) == -1) {
+        WEBRTC_TRACE(kTraceMemory, kTraceAudioMixerServer, _id,
+                     "failed PopMemory() call");
+        assert(false);
+        return;
         }
         audioFrame->sample_rate_hz_ = _outputFrequency;
         auto ret = (*participant)->GetAudioFrameWithMuted(_id, audioFrame);