C++11 declares a type safe null pointer

content/common/resource_messages.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 "content/common/resource_messages.h"
 
 #include "net/base/load_timing_info.h"
 #include "net/http/http_response_headers.h"
 
 namespace IPC {
 
 void ParamTraits<scoped_refptr<net::HttpResponseHeaders> >::Write(
     Message* m, const param_type& p) {
-  WriteParam(m, p.get() != NULL);
+  WriteParam(m, p.get() != nullptr);
   if (p.get()) {
     // Do not disclose Set-Cookie headers over IPC.
     p->Persist(m, net::HttpResponseHeaders::PERSIST_SANS_COOKIES);
   }
 }
 
 bool ParamTraits<scoped_refptr<net::HttpResponseHeaders> >::Read(
     const Message* m, PickleIterator* iter, param_type* r) {
   bool has_object;
   if (!ReadParam(m, iter, &has_object))
@@ skipping 103 matching lines @@
   return true;
 }
 
 void ParamTraits<storage::DataElement>::Log(const param_type& p,
                                             std::string* l) {
   l->append("<storage::DataElement>");
 }
 
 void ParamTraits<scoped_refptr<content::ResourceDevToolsInfo> >::Write(
     Message* m, const param_type& p) {
-  WriteParam(m, p.get() != NULL);
+  WriteParam(m, p.get() != nullptr);
   if (p.get()) {
     WriteParam(m, p->http_status_code);
     WriteParam(m, p->http_status_text);
     WriteParam(m, p->request_headers);
     WriteParam(m, p->response_headers);
     WriteParam(m, p->request_headers_text);
     WriteParam(m, p->response_headers_text);
   }
 }
 
@@ skipping 105 matching lines @@
   l->append(", ");
   LogParam(p.send_end, l);
   l->append(", ");
   LogParam(p.receive_headers_end, l);
   l->append(")");
 }
 
 void ParamTraits<scoped_refptr<content::ResourceRequestBody> >::Write(
     Message* m,
     const param_type& p) {
-  WriteParam(m, p.get() != NULL);
+  WriteParam(m, p.get() != nullptr);
   if (p.get()) {
     WriteParam(m, *p->elements());
     WriteParam(m, p->identifier());
   }
 }
 
 bool ParamTraits<scoped_refptr<content::ResourceRequestBody> >::Read(
     const Message* m,
     PickleIterator* iter,
     param_type* r) {
@@ skipping 13 matching lines @@
   (*r)->set_identifier(identifier);
   return true;
 }
 
 void ParamTraits<scoped_refptr<content::ResourceRequestBody> >::Log(
     const param_type& p, std::string* l) {
   l->append("<ResourceRequestBody>");
 }
 
 }  // namespace IPC