Avoid doing concurrent DNS resolves of the same hostname

net/base/tcp_pinger_unittest.cc

 // Copyright (c) 2006-2009 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 "base/ref_counted.h"
 #include "base/trace_event.h"
 #include "net/base/address_list.h"
 #include "net/base/host_resolver.h"
 #include "net/base/listen_socket.h"
 #include "net/base/net_errors.h"
@@ skipping 49 matching lines @@
     listen_sock_ = ListenSocket::Listen("127.0.0.1", listen_port_, this);
     if (listen_sock_.get()) break;
   }
   ASSERT_TRUE(listen_sock_.get() != NULL);
 }
 
 TEST_F(TCPPingerTest, Ping) {
   net::AddressList addr;
   net::HostResolver resolver;
 
-  int rv = resolver.Resolve("localhost", listen_port_, &addr, NULL);
+  int rv = resolver.Resolve("localhost", listen_port_, &addr, NULL, NULL);
   EXPECT_EQ(rv, net::OK);
 
   net::TCPPinger pinger(addr);
   rv = pinger.Ping();
   EXPECT_EQ(rv, net::OK);
 }
 
 TEST_F(TCPPingerTest, PingFail) {
   net::AddressList addr;
   net::HostResolver resolver;
 
   // "Kill" "server"
   listen_sock_ = NULL;
 
-  int rv = resolver.Resolve("localhost", listen_port_, &addr, NULL);
+  int rv = resolver.Resolve("localhost", listen_port_, &addr, NULL, NULL);
   EXPECT_EQ(rv, net::OK);
 
   net::TCPPinger pinger(addr);
   rv = pinger.Ping(base::TimeDelta::FromMilliseconds(100), 1);
   EXPECT_NE(rv, net::OK);
 }