Replace NULL with nullptr or null in webrtc/base/.

webrtc/base/firewallsocketserver.cc

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 103 matching lines @@
   if (manager_)
     manager_->AddServer(this);
 }
 
 FirewallSocketServer::~FirewallSocketServer() {
   if (manager_)
     manager_->RemoveServer(this);
 
   if (server_ && should_delete_server_) {
     delete server_;
-    server_ = NULL;
+    server_ = nullptr;
   }
 }
 
 void FirewallSocketServer::AddRule(bool allow, FirewallProtocol p,
                                    FirewallDirection d,
                                    const SocketAddress& addr) {
   SocketAddress any;
   if (d == FD_IN || d == FD_ANY) {
     AddRule(allow, p, any, addr);
   }
@@ skipping 68 matching lines @@
 void FirewallSocketServer::WakeUp() {
   return server_->WakeUp();
 }
 
 AsyncSocket* FirewallSocketServer::WrapSocket(AsyncSocket* sock, int type) {
   if (!sock ||
       (type == SOCK_STREAM && !tcp_sockets_enabled_) ||
       (type == SOCK_DGRAM && !udp_sockets_enabled_)) {
     LOG(LS_VERBOSE) << "FirewallSocketServer socket creation denied";
     delete sock;
-    return NULL;
+    return nullptr;
   }
   return new FirewallSocket(this, sock, type);
 }
 
 FirewallManager::FirewallManager() {
 }
 
 FirewallManager::~FirewallManager() {
   RTC_DCHECK(servers_.empty());
 }
@@ skipping 20 matching lines @@
 
 void FirewallManager::ClearRules() {
   CritScope scope(&crit_);
   for (std::vector<FirewallSocketServer*>::const_iterator it =
       servers_.begin(); it != servers_.end(); ++it) {
     (*it)->ClearRules();
   }
 }
 
 }  // namespace rtc