Add a command line flag to change the default number of parallel DNS requests...

net/proxy/proxy_script_fetcher_unittest.cc

 // Copyright (c) 2010 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/proxy/proxy_script_fetcher.h"
 
 #include "base/file_path.h"
 #include "base/compiler_specific.h"
 #include "base/path_service.h"
 #include "net/base/net_util.h"
@@ skipping 14 matching lines @@
 struct FetchResult {
   int code;
   string16 text;
 };
 
 // A non-mock URL request which can access http:// and file:// urls.
 class RequestContext : public URLRequestContext {
  public:
   RequestContext() {
     net::ProxyConfig no_proxy;
-    host_resolver_ = net::CreateSystemHostResolver();
+    host_resolver_ =
+        net::CreateSystemHostResolver(net::HostResolver::kDefaultParallelism);
     proxy_service_ = net::ProxyService::CreateFixed(no_proxy);
     ssl_config_service_ = new net::SSLConfigServiceDefaults;
 
     http_transaction_factory_ = new net::HttpCache(
         net::HttpNetworkLayer::CreateFactory(host_resolver_, proxy_service_,
             ssl_config_service_, NULL, NULL, NULL),
         net::HttpCache::DefaultBackend::InMemory(0));
   }
 
  private:
@@ skipping 273 matching lines @@
     string16 text;
     TestCompletionCallback callback;
     int result = pac_fetcher->Fetch(url, &text, &callback);
     EXPECT_EQ(ERR_IO_PENDING, result);
     EXPECT_EQ(OK, callback.WaitForResult());
     EXPECT_EQ(ASCIIToUTF16("This was encoded as UTF-16BE.\n"), text);
   }
 }
 
 }  // namespace net