C++11 declares a type safe null pointer

content/common/gpu/media/vaapi_video_decode_accelerator.h

 // Copyright (c) 2012 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.
 //
 // This file contains an implementation of VideoDecoderAccelerator
 // that utilizes hardware video decoder present on Intel CPUs.
 
 #ifndef CONTENT_COMMON_GPU_MEDIA_VAAPI_VIDEO_DECODE_ACCELERATOR_H_
 #define CONTENT_COMMON_GPU_MEDIA_VAAPI_VIDEO_DECODE_ACCELERATOR_H_
 
@@ skipping 231 matching lines @@
   scoped_ptr<base::WeakPtrFactory<Client> > client_ptr_factory_;
   base::WeakPtr<Client> client_;
 
   scoped_ptr<VaapiWrapper> vaapi_wrapper_;
 
   // Comes after vaapi_wrapper_ to ensure its destructor is executed before
   // vaapi_wrapper_ is destroyed.
   scoped_ptr<VaapiH264Decoder> decoder_;
   base::Thread decoder_thread_;
   // Use this to post tasks to |decoder_thread_| instead of
-  // |decoder_thread_.message_loop()| because the latter will be NULL once
+  // |decoder_thread_.message_loop()| because the latter will be nullptr once
   // |decoder_thread_.Stop()| returns.
   scoped_refptr<base::MessageLoopProxy> decoder_thread_proxy_;
 
   int num_frames_at_client_;
   int num_stream_bufs_at_decoder_;
 
   // Whether we are waiting for any pending_output_cbs_ to be run before
   // NotifyingFlushDone.
   bool finish_flush_pending_;
 
   // Decoder requested a new surface set and we are waiting for all the surfaces
   // to be returned before we can free them.
   bool awaiting_va_surfaces_recycle_;
 
   // Last requested number/resolution of output picture buffers.
   size_t requested_num_pics_;
   gfx::Size requested_pic_size_;
 
   // The WeakPtrFactory for |weak_this_|.
   base::WeakPtrFactory<VaapiVideoDecodeAccelerator> weak_this_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(VaapiVideoDecodeAccelerator);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_MEDIA_VAAPI_VIDEO_DECODE_ACCELERATOR_H_