Replace NULL with nullptr in all C++ files.

webrtc/voice_engine/voice_engine_impl.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 13 matching lines @@
 namespace webrtc {
 
 // Counter to be ensure that we can add a correct ID in all static trace
 // methods. It is not the nicest solution, especially not since we already
 // have a counter in VoEBaseImpl. In other words, there is room for
 // improvement here.
 static int32_t gVoiceEngineInstanceCounter = 0;
 
 VoiceEngine* GetVoiceEngine() {
   VoiceEngineImpl* self = new VoiceEngineImpl();
-  if (self != NULL) {
+  if (self != nullptr) {
     self->AddRef();  // First reference.  Released in VoiceEngine::Delete.
     gVoiceEngineInstanceCounter++;
   }
   return self;
 }
 
 int VoiceEngineImpl::AddRef() {
   return ++_ref_count;
 }
 
@@ skipping 58 matching lines @@
 }
 
 int VoiceEngine::SetTraceCallback(TraceCallback* callback) {
   WEBRTC_TRACE(kTraceApiCall, kTraceVoice,
                VoEId(gVoiceEngineInstanceCounter, -1),
                "SetTraceCallback(callback=0x%x)", callback);
   return (Trace::SetTraceCallback(callback));
 }
 
 bool VoiceEngine::Delete(VoiceEngine*& voiceEngine) {
-  if (voiceEngine == NULL)
+  if (voiceEngine == nullptr)
     return false;
 
   VoiceEngineImpl* s = static_cast<VoiceEngineImpl*>(voiceEngine);
   // Release the reference that was added in GetVoiceEngine.
   int ref = s->Release();
-  voiceEngine = NULL;
+  voiceEngine = nullptr;
 
   if (ref != 0) {
     WEBRTC_TRACE(
         kTraceWarning, kTraceVoice, -1,
         "VoiceEngine::Delete did not release the very last reference.  "
         "%d references remain.",
         ref);
   }
 
   return true;
@@ skipping 14 matching lines @@
 
 std::string VoiceEngine::GetVersionString() {
   std::string version = "VoiceEngine 4.1.0";
 #ifdef WEBRTC_EXTERNAL_TRANSPORT
   version += " (External transport build)";
 #endif
   return version;
 }
 
 }  // namespace webrtc