C++11 declares a type safe null pointer

content/common/cursors/webcursor_ozone.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/cursors/webcursor.h"
 
 #include "third_party/WebKit/public/platform/WebCursorInfo.h"
 #include "ui/base/cursor/cursor.h"
 #include "ui/base/cursor/cursor_util.h"
 #include "ui/ozone/public/cursor_factory_ozone.h"
@@ skipping 16 matching lines @@
 
 void WebCursor::SetDisplayInfo(const gfx::Display& display) {
   if (rotation_ == display.rotation() &&
       device_scale_factor_ == display.device_scale_factor())
     return;
 
   device_scale_factor_ = display.device_scale_factor();
   rotation_ = display.rotation();
   if (platform_cursor_)
     ui::CursorFactoryOzone::GetInstance()->UnrefImageCursor(platform_cursor_);
-  platform_cursor_ = NULL;
+  platform_cursor_ = nullptr;
   // It is not necessary to recreate platform_cursor_ yet, since it will be
   // recreated on demand when GetPlatformCursor is called.
 }
 
 void WebCursor::InitPlatformData() {
-  platform_cursor_ = NULL;
+  platform_cursor_ = nullptr;
   device_scale_factor_ = 1.f;
   rotation_ = gfx::Display::ROTATE_0;
 }
 
 bool WebCursor::SerializePlatformData(Pickle* pickle) const {
   return true;
 }
 
 bool WebCursor::DeserializePlatformData(PickleIterator* iter) {
   return true;
 }
 
 bool WebCursor::IsPlatformDataEqual(const WebCursor& other) const {
   return true;
 }
 
 void WebCursor::CleanupPlatformData() {
   if (platform_cursor_) {
     ui::CursorFactoryOzone::GetInstance()->UnrefImageCursor(platform_cursor_);
-    platform_cursor_ = NULL;
+    platform_cursor_ = nullptr;
   }
 }
 
 void WebCursor::CopyPlatformData(const WebCursor& other) {
   if (platform_cursor_)
     ui::CursorFactoryOzone::GetInstance()->UnrefImageCursor(platform_cursor_);
   platform_cursor_ = other.platform_cursor_;
   if (platform_cursor_)
     ui::CursorFactoryOzone::GetInstance()->RefImageCursor(platform_cursor_);
 
   device_scale_factor_ = other.device_scale_factor_;
 }
 
 }  // namespace content