Replace NULL with nullptr in all C++ files.

webrtc/modules/desktop_capture/mac/full_screen_chrome_window_detector.cc

 /*
  *  Copyright (c) 2014 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 10 matching lines @@
 
 
 namespace webrtc {
 
 namespace {
 
 const int64_t kUpdateIntervalMs = 500;
 
 std::string GetWindowTitle(CGWindowID id) {
   CFArrayRef window_id_array =
-      CFArrayCreate(NULL, reinterpret_cast<const void **>(&id), 1, NULL);
+      CFArrayCreate(nullptr, reinterpret_cast<const void**>(&id), 1, nullptr);
   CFArrayRef window_array =
       CGWindowListCreateDescriptionFromArray(window_id_array);
   std::string title;
 
   if (window_array && CFArrayGetCount(window_array)) {
     CFDictionaryRef window = reinterpret_cast<CFDictionaryRef>(
         CFArrayGetValueAtIndex(window_array, 0));
     CFStringRef title_ref =  reinterpret_cast<CFStringRef>(
         CFDictionaryGetValue(window, kCGWindowName));
 
     if (title_ref)
       rtc::ToUtf8(title_ref, &title);
   }
   CFRelease(window_id_array);
   CFRelease(window_array);
 
   return title;
 }
 
 int GetWindowOwnerPid(CGWindowID id) {
   CFArrayRef window_id_array =
-      CFArrayCreate(NULL, reinterpret_cast<const void **>(&id), 1, NULL);
+      CFArrayCreate(nullptr, reinterpret_cast<const void**>(&id), 1, nullptr);
   CFArrayRef window_array =
       CGWindowListCreateDescriptionFromArray(window_id_array);
   int pid = 0;
 
   if (window_array && CFArrayGetCount(window_array)) {
     CFDictionaryRef window = reinterpret_cast<CFDictionaryRef>(
         CFArrayGetValueAtIndex(window_array, 0));
     CFNumberRef pid_ref =  reinterpret_cast<CFNumberRef>(
         CFDictionaryGetValue(window, kCGWindowOwnerPID));
 
@@ skipping 117 matching lines @@
       previous_window_list_.clear();
       return;
     }
 
     GetWindowList(&current_window_list_, false);
     last_update_time_ns_ = rtc::TimeNanos();
   }
 }
 
 }  // namespace webrtc