Use nullptr instead of 0 in WebAudio

Source/platform/audio/mac/FFTFrameMac.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 24 matching lines @@
 #if OS(MACOSX)
 
 #include "platform/audio/FFTFrame.h"
 
 #include "platform/audio/VectorMath.h"
 
 namespace blink {
 
 const int kMaxFFTPow2Size = 24;
 
-FFTSetup* FFTFrame::fftSetups = 0;
+FFTSetup* FFTFrame::fftSetups = nullptr;
 
 // Normal constructor: allocates for a given fftSize
 FFTFrame::FFTFrame(unsigned fftSize)
     : m_realData(fftSize)
     , m_imagData(fftSize)
 {
     m_FFTSize = fftSize;
     m_log2FFTSize = static_cast<unsigned>(log2(fftSize));
 
     // We only allow power of two
@@ skipping 87 matching lines @@
 {
     if (!fftSetups)
         return;
 
     for (int i = 0; i < kMaxFFTPow2Size; ++i) {
         if (fftSetups[i])
             vDSP_destroy_fftsetup(fftSetups[i]);
     }
 
     free(fftSetups);
-    fftSetups = 0;
+    fftSetups = nullptr;
 }
 
 } // namespace blink
 
 #endif // #if OS(MACOSX)
 
 #endif // ENABLE(WEB_AUDIO)