Replace NULL with nullptr in all C++ files.

webrtc/modules/desktop_capture/mac/scoped_pixel_buffer_object.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.
  */
 
 #include "webrtc/modules/desktop_capture/mac/scoped_pixel_buffer_object.h"
 
 #include <stddef.h>
 
 namespace webrtc {
 
 ScopedPixelBufferObject::ScopedPixelBufferObject()
-    : cgl_context_(NULL),
-      pixel_buffer_object_(0) {
-}
+    : cgl_context_(nullptr), pixel_buffer_object_(0) {}
 
 ScopedPixelBufferObject::~ScopedPixelBufferObject() {
   Release();
 }
 
 bool ScopedPixelBufferObject::Init(CGLContextObj cgl_context,
                                       int size_in_bytes) {
   cgl_context_ = cgl_context;
   CGLContextObj CGL_MACRO_CONTEXT = cgl_context_;
   glGenBuffersARB(1, &pixel_buffer_object_);
   if (glGetError() == GL_NO_ERROR) {
     glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, pixel_buffer_object_);
-    glBufferDataARB(GL_PIXEL_PACK_BUFFER_ARB, size_in_bytes, NULL,
+    glBufferDataARB(GL_PIXEL_PACK_BUFFER_ARB, size_in_bytes, nullptr,
                     GL_STREAM_READ_ARB);
     glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, 0);
     if (glGetError() != GL_NO_ERROR) {
       Release();
     }
   } else {
-    cgl_context_ = NULL;
+    cgl_context_ = nullptr;
     pixel_buffer_object_ = 0;
   }
   return pixel_buffer_object_ != 0;
 }
 
 void ScopedPixelBufferObject::Release() {
   if (pixel_buffer_object_) {
     CGLContextObj CGL_MACRO_CONTEXT = cgl_context_;
     glDeleteBuffersARB(1, &pixel_buffer_object_);
-    cgl_context_ = NULL;
+    cgl_context_ = nullptr;
     pixel_buffer_object_ = 0;
   }
 }
 
 }  // namespace webrtc