Rewrite scoped_ptr<T>(NULL) to use the default ctor in net/.

net/dns/dns_socket_pool.cc

 // 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.
 
 #include "net/dns/dns_socket_pool.h"
 
 #include "base/logging.h"
 #include "base/rand_util.h"
 #include "base/stl_util.h"
 #include "net/base/address_list.h"
@@ skipping 169 matching lines @@
 }
 
 scoped_ptr<DatagramClientSocket> DefaultDnsSocketPool::AllocateSocket(
     unsigned server_index) {
   DCHECK_LT(server_index, pools_.size());
   SocketVector& pool = pools_[server_index];
 
   FillPool(server_index, kAllocateMinSize);
   if (pool.size() == 0) {
     LOG(WARNING) << "No DNS sockets available in pool " << server_index << "!";
-    return scoped_ptr<DatagramClientSocket>(NULL);
+    return scoped_ptr<DatagramClientSocket>();
   }
 
   if (pool.size() < kAllocateMinSize) {
     LOG(WARNING) << "Low DNS port entropy: wanted " << kAllocateMinSize
                  << " sockets to choose from, but only have " << pool.size()
                  << " in pool " << server_index << ".";
   }
 
   unsigned socket_index = base::RandInt(0, pool.size() - 1);
   DatagramClientSocket* socket = pool[socket_index];
@@ skipping 24 matching lines @@
   for (unsigned pool_index = pool.size(); pool_index < size; ++pool_index) {
     DatagramClientSocket* socket =
         CreateConnectedSocket(server_index).release();
     if (!socket)
       break;
     pool.push_back(socket);
   }
 }
 
 } // namespace net