replace NULL->nullptr in src/remoting.

remoting/protocol/buffered_socket_writer.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 REMOTING_PROTOCOL_BUFFERED_SOCKET_WRITER_H_
 #define REMOTING_PROTOCOL_BUFFERED_SOCKET_WRITER_H_
 
 #include <list>
 
 #include "base/callback.h"
@@ skipping 55 matching lines @@
   int buffer_size_;
 
   // Removes element from the front of the queue and returns |done_task| for
   // that element. Called from AdvanceBufferPosition() implementation, which
   // then returns result of this function to its caller.
   base::Closure PopQueue();
 
   // Following three methods must be implemented in child classes.
 
   // Returns next packet that needs to be written to the socket. Implementation
-  // must set |*buffer| to NULL if there is nothing left in the queue.
+  // must set |*buffer| to nullptr if there is nothing left in the queue.
   virtual void GetNextPacket(net::IOBuffer** buffer, int* size) = 0;
 
   // Returns closure that must be executed or null closure if the last write
   // didn't complete any messages.
   virtual base::Closure AdvanceBufferPosition(int written) = 0;
 
   // This method is called whenever there is an error writing to the socket.
   virtual void OnError(int result) = 0;
 
  private:
@@ skipping 36 matching lines @@
  protected:
   void GetNextPacket(net::IOBuffer** buffer, int* size) override;
   base::Closure AdvanceBufferPosition(int written) override;
   void OnError(int result) override;
 };
 
 }  // namespace protocol
 }  // namespace remoting
 
 #endif  // REMOTING_PROTOCOL_BUFFERED_SOCKET_WRITER_H_