C++11 declares a type safe null pointer

content/common/gpu/gpu_channel.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.
 
 #ifndef CONTENT_COMMON_GPU_GPU_CHANNEL_H_
 #define CONTENT_COMMON_GPU_GPU_CHANNEL_H_
 
 #include <deque>
 #include <string>
 
@@ skipping 114 matching lines @@
 
   // Called to remove a listener for a particular message routing ID.
   void RemoveRoute(int32 route_id);
 
   gpu::PreemptionFlag* GetPreemptionFlag();
 
   bool handle_messages_scheduled() const { return handle_messages_scheduled_; }
   uint64 messages_processed() const { return messages_processed_; }
 
   // If |preemption_flag->IsSet()|, any stub on this channel
-  // should stop issuing GL commands. Setting this to NULL stops deferral.
+  // should stop issuing GL commands. Setting this to nullptr stops deferral.
   void SetPreemptByFlag(
       scoped_refptr<gpu::PreemptionFlag> preemption_flag);
 
   void CacheShader(const std::string& key, const std::string& shader);
 
   void AddFilter(IPC::MessageFilter* filter);
   void RemoveFilter(IPC::MessageFilter* filter);
 
   uint64 GetMemoryUsage();
 
@@ skipping 27 matching lines @@
   GpuChannelManager* gpu_channel_manager_;
 
   scoped_ptr<IPC::SyncChannel> channel_;
 
   uint64 messages_processed_;
 
   // Whether the processing of IPCs on this channel is stalled and we should
   // preempt other GpuChannels.
   scoped_refptr<gpu::PreemptionFlag> preempting_flag_;
 
-  // If non-NULL, all stubs on this channel should stop processing GL
+  // If non-nullptr, all stubs on this channel should stop processing GL
   // commands (via their GpuScheduler) when preempted_flag_->IsSet()
   scoped_refptr<gpu::PreemptionFlag> preempted_flag_;
 
   std::deque<IPC::Message*> deferred_messages_;
 
   // The id of the client who is on the other side of the channel.
   int client_id_;
 
   // Uniquely identifies the channel within this GPU process.
   std::string channel_id_;
@@ skipping 29 matching lines @@
   // that any WeakPtrs to Controller are invalidated before its members
   // variable's destructors are executed, rendering them invalid.
   base::WeakPtrFactory<GpuChannel> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuChannel);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_GPU_CHANNEL_H_