Avoid doing concurrent DNS resolves of the same hostname

net/proxy/proxy_resolver_v8_unittest.cc

 // Copyright (c) 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/file_util.h"
 #include "base/string_util.h"
 #include "base/path_service.h"
 #include "googleurl/src/gurl.h"
+#include "net/base/host_resolver.h"
 #include "net/base/net_errors.h"
 #include "net/proxy/proxy_resolver_v8.h"
 #include "net/proxy/proxy_info.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
 // Javascript bindings for ProxyResolverV8, which returns mock values.
 // Each time one of the bindings is called into, we push the input into a
 // list, for later verification.
@@ skipping 351 matching lines @@
   EXPECT_EQ("3", bindings->dns_resolves[6]);
 
   EXPECT_EQ("arg1", bindings->dns_resolves[7]);
 
   // MyIpAddress was called two times.
   EXPECT_EQ(2, bindings->my_ip_address_count);
 }
 
 TEST(ProxyResolverV8DefaultBindingsTest, DnsResolve) {
   // Get a hold of a DefaultJSBindings* (it is a hidden impl class).
-  net::ProxyResolverV8 resolver;
-  net::ProxyResolverV8::JSBindings* bindings = resolver.js_bindings();
+  net::HostResolver host_resolver;
+  scoped_ptr<net::ProxyResolverV8::JSBindings> bindings(
+      net::ProxyResolverV8::CreateDefaultBindings(&host_resolver, NULL));
 
   // Considered an error.
   EXPECT_EQ("", bindings->DnsResolve(""));
 
   const struct {
     const char* input;
     const char* expected;
   } tests[] = {
     {"www.google.com", "127.0.0.1"},
     {".", ""},
@@ skipping 29 matching lines @@
     // For now we just check that it maps to 127.0.0.1.
     std::string expected = tests[i].expected;
     if (expected == "")
       expected = "127.0.0.1";
     EXPECT_EQ(expected, actual);
   }
 }
 
 TEST(ProxyResolverV8DefaultBindingsTest, MyIpAddress) {
   // Get a hold of a DefaultJSBindings* (it is a hidden impl class).
-  net::ProxyResolverV8 resolver;
-  net::ProxyResolverV8::JSBindings* bindings = resolver.js_bindings();
+  net::HostResolver host_resolver;
+  scoped_ptr<net::ProxyResolverV8::JSBindings> bindings(
+      net::ProxyResolverV8::CreateDefaultBindings(&host_resolver, NULL));
 
   // Our ip address is always going to be 127.0.0.1, since we are using a
   // mock host mapper when running in unit-test mode.
   std::string my_ip_address = bindings->MyIpAddress();
 
   EXPECT_EQ("127.0.0.1", my_ip_address);
 }