Bypass the DataReductionProxy for all POST requests

net/proxy/proxy_service_unittest.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 "net/proxy/proxy_service.h"
 
 #include <cstdarg>
+#include <string>
 #include <vector>
 
 #include "base/format_macros.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "net/base/load_flags.h"
 #include "net/base/net_errors.h"
 #include "net/base/proxy_delegate.h"
@@ skipping 146 matching lines @@
 // A test network delegate that exercises the OnResolveProxy callback.
 class TestResolveProxyDelegate : public ProxyDelegate {
  public:
   TestResolveProxyDelegate()
       : on_resolve_proxy_called_(false),
         add_proxy_(false),
         remove_proxy_(false),
         proxy_service_(nullptr) {}
 
   void OnResolveProxy(const GURL& url,
+                      const std::string& method,
                       int load_flags,
                       const ProxyService& proxy_service,
                       ProxyInfo* result) override {
     on_resolve_proxy_called_ = true;
     proxy_service_ = &proxy_service;
     DCHECK(!add_proxy_ || !remove_proxy_);
     if (add_proxy_) {
       result->UseNamedProxy("delegate_proxy.com");
     } else if (remove_proxy_) {
       result->UseDirect();

[mmenke, 2016/03/02 22:53:45]

Should record the method, and have a test that makes sure we send it.  Can just
modify OnResolveProxyCallbackAddProxy(), or add a new one.

[RyanSturm, 2016/03/03 18:54:31]

Done.

     }
   }
 
   bool on_resolve_proxy_called() const {
     return on_resolve_proxy_called_;
   }
 
   void set_add_proxy(bool add_proxy) {
     add_proxy_ = add_proxy;
   }
@@ skipping 31 matching lines @@
 };
 
 // A test network delegate that exercises the OnProxyFallback callback.
 class TestProxyFallbackProxyDelegate : public ProxyDelegate {
  public:
   TestProxyFallbackProxyDelegate()
       : on_proxy_fallback_called_(false), proxy_fallback_net_error_(OK) {}
 
   // ProxyDelegate implementation:
   void OnResolveProxy(const GURL& url,
+                      const std::string& method,
                       int load_flags,
                       const ProxyService& proxy_service,
                       ProxyInfo* result) override {}
   void OnTunnelConnectCompleted(const HostPortPair& endpoint,
                                 const HostPortPair& proxy_server,
                                 int net_error) override {}
   void OnFallback(const ProxyServer& bad_proxy, int net_error) override {
     proxy_server_ = bad_proxy;
     proxy_fallback_net_error_ = net_error;
     on_proxy_fallback_called_ = true;
@@ skipping 99 matching lines @@
   return GetJobsForURLs(map, urls);
 }
 
 }  // namespace
 
 TEST_F(ProxyServiceTest, Direct) {
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
   ProxyService service(
       make_scoped_ptr(new MockProxyConfigService(ProxyConfig::CreateDirect())),
-      make_scoped_ptr(factory), NULL);
+      make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   ProxyInfo info;
   TestCompletionCallback callback;
   BoundTestNetLog log;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(),
-                                NULL, NULL, log.bound());
+  int rv =
+      service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                           callback.callback(), nullptr, nullptr, log.bound());
   EXPECT_EQ(OK, rv);
   EXPECT_TRUE(factory->pending_requests().empty());
 
   EXPECT_TRUE(info.is_direct());
   EXPECT_TRUE(info.proxy_resolve_start_time().is_null());
   EXPECT_TRUE(info.proxy_resolve_end_time().is_null());
 
   // Check the NetLog was filled correctly.
   TestNetLogEntry::List entries;
   log.GetEntries(&entries);
 
   EXPECT_EQ(3u, entries.size());
   EXPECT_TRUE(LogContainsBeginEvent(
       entries, 0, NetLog::TYPE_PROXY_SERVICE));
   EXPECT_TRUE(LogContainsEvent(
       entries, 1, NetLog::TYPE_PROXY_SERVICE_RESOLVED_PROXY_LIST,
       NetLog::PHASE_NONE));
   EXPECT_TRUE(LogContainsEndEvent(
       entries, 2, NetLog::TYPE_PROXY_SERVICE));
 }
 
 TEST_F(ProxyServiceTest, OnResolveProxyCallbackAddProxy) {
   ProxyConfig config;
   config.proxy_rules().ParseFromString("foopy1:8080");
   config.set_auto_detect(false);
   config.proxy_rules().bypass_rules.ParseFromString("*.org");
 
   ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                       nullptr, NULL);
+                       nullptr, nullptr);
 
   GURL url("http://www.google.com/");
   GURL bypass_url("http://internet.org");
 
   ProxyInfo info;
   TestCompletionCallback callback;
   BoundTestNetLog log;
 
   // First, warm up the ProxyService.
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(),
-                                NULL, NULL, log.bound());
+  int rv =
+      service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                           callback.callback(), nullptr, nullptr, log.bound());
   EXPECT_EQ(OK, rv);
 
   // Verify that network delegate is invoked.
   TestResolveProxyDelegate delegate;
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(), NULL,
-                            &delegate, log.bound());
+  rv = service.ResolveProxy(url, "GET", LOAD_NORMAL, &info, callback.callback(),
+                            nullptr, &delegate, log.bound());
   EXPECT_TRUE(delegate.on_resolve_proxy_called());
   EXPECT_EQ(&service, delegate.proxy_service());
 
   // Verify that the ProxyDelegate's behavior is stateless across
   // invocations of ResolveProxy. Start by having the callback add a proxy
   // and checking that subsequent jobs are not affected.
   delegate.set_add_proxy(true);
 
   // Callback should interpose:
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(), NULL,
-                            &delegate, log.bound());
+  rv = service.ResolveProxy(url, "GET", LOAD_NORMAL, &info, callback.callback(),
+                            nullptr, &delegate, log.bound());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ(info.proxy_server().host_port_pair().host(), "delegate_proxy.com");
   delegate.set_add_proxy(false);
 
   // Check non-bypassed URL:
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(), NULL,
-                            &delegate, log.bound());
+  rv = service.ResolveProxy(url, "GET", LOAD_NORMAL, &info, callback.callback(),
+                            nullptr, &delegate, log.bound());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ(info.proxy_server().host_port_pair().host(), "foopy1");
 
   // Check bypassed URL:
-  rv = service.ResolveProxy(bypass_url, LOAD_NORMAL, &info, callback.callback(),
-                            NULL, &delegate, log.bound());
+  rv = service.ResolveProxy(bypass_url, "GET", LOAD_NORMAL, &info,
+                            callback.callback(), nullptr, &delegate,
+                            log.bound());
   EXPECT_TRUE(info.is_direct());
 }
 
 TEST_F(ProxyServiceTest, OnResolveProxyCallbackRemoveProxy) {
   // Same as OnResolveProxyCallbackAddProxy, but verify that the
   // ProxyDelegate's behavior is stateless across invocations after it
   // *removes* a proxy.
   ProxyConfig config;
   config.proxy_rules().ParseFromString("foopy1:8080");
   config.set_auto_detect(false);
   config.proxy_rules().bypass_rules.ParseFromString("*.org");
 
   ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                       nullptr, NULL);
+                       nullptr, nullptr);
 
   GURL url("http://www.google.com/");
   GURL bypass_url("http://internet.org");
 
   ProxyInfo info;
   TestCompletionCallback callback;
   BoundTestNetLog log;
 
   // First, warm up the ProxyService.
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(),
-                                NULL, NULL, log.bound());
+  int rv =
+      service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                           callback.callback(), nullptr, nullptr, log.bound());
   EXPECT_EQ(OK, rv);
 
   TestResolveProxyDelegate delegate;
   delegate.set_remove_proxy(true);
 
   // Callback should interpose:
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(), NULL,
-                            &delegate, log.bound());
+  rv = service.ResolveProxy(url, "GET", LOAD_NORMAL, &info, callback.callback(),
+                            nullptr, &delegate, log.bound());
   EXPECT_TRUE(info.is_direct());
   delegate.set_remove_proxy(false);
 
   // Check non-bypassed URL:
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(), NULL,
-                            &delegate, log.bound());
+  rv = service.ResolveProxy(url, "GET", LOAD_NORMAL, &info, callback.callback(),
+                            nullptr, &delegate, log.bound());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ(info.proxy_server().host_port_pair().host(), "foopy1");
 
   // Check bypassed URL:
-  rv = service.ResolveProxy(bypass_url, LOAD_NORMAL, &info, callback.callback(),
-                            NULL, &delegate, log.bound());
+  rv = service.ResolveProxy(bypass_url, "GET", LOAD_NORMAL, &info,
+                            callback.callback(), nullptr, &delegate,
+                            log.bound());
   EXPECT_TRUE(info.is_direct());
 }
 
 TEST_F(ProxyServiceTest, PAC) {
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   ProxyInfo info;
   TestCompletionCallback callback;
   ProxyService::PacRequest* request;
   BoundTestNetLog log;
 
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(),
-                                &request, NULL, log.bound());
+  int rv =
+      service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                           callback.callback(), &request, nullptr, log.bound());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(LOAD_STATE_RESOLVING_PROXY_FOR_URL, service.GetLoadState(request));
 
   ASSERT_EQ(1u, factory->pending_requests().size());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
@@ skipping 31 matching lines @@
 // or its reference section.
 TEST_F(ProxyServiceTest, PAC_NoIdentityOrHash) {
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://username:password@www.google.com/?ref#hash#hash");
 
   ProxyInfo info;
   TestCompletionCallback callback;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   // The URL should have been simplified, stripping the username/password/hash.
   EXPECT_EQ(GURL("http://www.google.com/?ref"),
             resolver.pending_jobs()[0]->url());
 
   // We end here without ever completing the request -- destruction of
   // ProxyService will cancel the outstanding request.
 }
 
 TEST_F(ProxyServiceTest, PAC_FailoverWithoutDirect) {
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // Set the result in proxy resolver.
   resolver.pending_jobs()[0]->results()->UseNamedProxy("foopy:8080");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy:8080", info.proxy_server().ToURI());
   EXPECT_TRUE(info.did_use_pac_script());
 
   EXPECT_FALSE(info.proxy_resolve_start_time().is_null());
   EXPECT_FALSE(info.proxy_resolve_end_time().is_null());
   EXPECT_LE(info.proxy_resolve_start_time(), info.proxy_resolve_end_time());
 
   // Now, imagine that connecting to foopy:8080 fails: there is nothing
   // left to fallback to, since our proxy list was NOT terminated by
   // DIRECT.
   TestResolveProxyDelegate proxy_delegate;
   TestCompletionCallback callback2;
   ProxyServer expected_proxy_server = info.proxy_server();
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback2.callback(), NULL, &proxy_delegate, BoundNetLog());
+      url, "GET", LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback2.callback(), nullptr, &proxy_delegate, BoundNetLog());
   // ReconsiderProxyAfterError returns error indicating nothing left.
   EXPECT_EQ(ERR_FAILED, rv);
   EXPECT_TRUE(info.is_empty());
 }
 
 // Test that if the execution of the PAC script fails (i.e. javascript runtime
 // error), and the PAC settings are non-mandatory, that we fall-back to direct.
 TEST_F(ProxyServiceTest, PAC_RuntimeError) {
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://this-causes-js-error/");
 
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // Simulate a failure in the PAC executor.
@@ skipping 30 matching lines @@
 // The important check of this test is to make sure that DIRECT is not somehow
 // cached as being a bad proxy.
 TEST_F(ProxyServiceTest, PAC_FailoverAfterDirect) {
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // Set the result in proxy resolver.
   resolver.pending_jobs()[0]->results()->UsePacString(
       "DIRECT ; PROXY foobar:10 ; DIRECT ; PROXY foobar:20");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_TRUE(info.is_direct());
 
   // Fallback 1.
   TestCompletionCallback callback2;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback2.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback2.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foobar:10", info.proxy_server().ToURI());
 
   // Fallback 2.
   TestResolveProxyDelegate proxy_delegate;
   ProxyServer expected_proxy_server3 = info.proxy_server();
   TestCompletionCallback callback3;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback3.callback(), NULL, &proxy_delegate, BoundNetLog());
+      url, "GET", LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback3.callback(), nullptr, &proxy_delegate, BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_TRUE(info.is_direct());
 
   // Fallback 3.
   ProxyServer expected_proxy_server4 = info.proxy_server();
   TestCompletionCallback callback4;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback4.callback(), NULL, &proxy_delegate, BoundNetLog());
+      url, "GET", LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback4.callback(), nullptr, &proxy_delegate, BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foobar:20", info.proxy_server().ToURI());
 
   // Fallback 4 -- Nothing to fall back to!
   ProxyServer expected_proxy_server5 = info.proxy_server();
   TestCompletionCallback callback5;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback5.callback(), NULL, &proxy_delegate, BoundNetLog());
+      url, "GET", LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback5.callback(), nullptr, &proxy_delegate, BoundNetLog());
   EXPECT_EQ(ERR_FAILED, rv);
   EXPECT_TRUE(info.is_empty());
 }
 
 TEST_F(ProxyServiceTest, PAC_ConfigSourcePropagates) {
   // Test whether the ProxyConfigSource set by the ProxyConfigService is applied
   // to ProxyInfo after the proxy is resolved via a PAC script.
   ProxyConfig config =
       ProxyConfig::CreateFromCustomPacURL(GURL("http://foopy/proxy.pac"));
   config.set_source(PROXY_CONFIG_SOURCE_TEST);
 
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   // Resolve something.
   GURL url("http://www.google.com/");
   ProxyInfo info;
   TestCompletionCallback callback;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback.callback(), nullptr, nullptr,
+                                BoundNetLog());
   ASSERT_EQ(ERR_IO_PENDING, rv);
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
   ASSERT_EQ(1u, resolver.pending_jobs().size());
 
   // Set the result in proxy resolver.
   resolver.pending_jobs()[0]->results()->UseNamedProxy("foopy");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   EXPECT_EQ(OK, callback.WaitForResult());
   EXPECT_EQ(PROXY_CONFIG_SOURCE_TEST, info.config_source());
@@ skipping 10 matching lines @@
   // javascript runtime error while calling FindProxyForURL().
 
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   // Start first resolve request.
   GURL url("http://www.google.com/");
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // Fail the first resolve request in MockAsyncProxyResolver.
   resolver.pending_jobs()[0]->CompleteNow(ERR_FAILED);
 
   // Although the proxy resolver failed the request, ProxyService implicitly
   // falls-back to DIRECT.
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_TRUE(info.is_direct());
 
   // Failed PAC executions still have proxy resolution times.
   EXPECT_FALSE(info.proxy_resolve_start_time().is_null());
   EXPECT_FALSE(info.proxy_resolve_end_time().is_null());
   EXPECT_LE(info.proxy_resolve_start_time(), info.proxy_resolve_end_time());
 
   // The second resolve request will try to run through the proxy resolver,
   // regardless of whether the first request failed in it.
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback2.callback(), NULL,
-                            NULL, BoundNetLog());
+  rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                            callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // This time we will have the resolver succeed (perhaps the PAC script has
   // a dependency on the current time).
   resolver.pending_jobs()[0]->results()->UseNamedProxy("foopy_valid:8080");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
@@ skipping 13 matching lines @@
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
                        make_scoped_ptr(factory), nullptr);
 
   // Start first resolve request.
   GURL url("http://www.google.com/");
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(url, net::LOAD_NORMAL, &info, callback1.callback(),
-                           nullptr, nullptr, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), net::LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, factory->pending_requests().size());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // Fail the first resolve request in MockAsyncProxyResolver.
   resolver.pending_jobs()[0]->CompleteNow(ERR_PAC_SCRIPT_TERMINATED);
 
   // Although the proxy resolver failed the request, ProxyService implicitly
   // falls-back to DIRECT.
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_TRUE(info.is_direct());
 
   // Failed PAC executions still have proxy resolution times.
   EXPECT_FALSE(info.proxy_resolve_start_time().is_null());
   EXPECT_FALSE(info.proxy_resolve_end_time().is_null());
   EXPECT_LE(info.proxy_resolve_start_time(), info.proxy_resolve_end_time());
 
   // With no other requests, the ProxyService waits for a new request before
   // initializing a new ProxyResolver.
   EXPECT_TRUE(factory->pending_requests().empty());
 
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(url, net::LOAD_NORMAL, &info, callback2.callback(),
-                            nullptr, nullptr, BoundNetLog());
+  rv = service.ResolveProxy(url, std::string(), net::LOAD_NORMAL, &info,
+                            callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, factory->pending_requests().size());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
@@ skipping 19 matching lines @@
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
                        make_scoped_ptr(factory), nullptr);
 
   // Start two resolve requests.
   GURL url1("http://www.google.com/");
   GURL url2("https://www.google.com/");
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(url1, net::LOAD_NORMAL, &info, callback1.callback(),
-                           nullptr, nullptr, BoundNetLog());
+  int rv = service.ResolveProxy(url1, std::string(), net::LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(url2, net::LOAD_NORMAL, &info, callback2.callback(),
-                            nullptr, nullptr, BoundNetLog());
+  rv = service.ResolveProxy(url2, std::string(), net::LOAD_NORMAL, &info,
+                            callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, factory->pending_requests().size());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   JobMap jobs = GetPendingJobsForURLs(resolver, url1, url2);
 
   // Fail the first resolve request in MockAsyncProxyResolver.
@@ skipping 37 matching lines @@
   ProxyConfig config(
       ProxyConfig::CreateFromCustomPacURL(GURL("http://foopy/proxy.pac")));
   config.set_pac_mandatory(true);
 
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
 
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   // Start first resolve request.
   GURL url("http://www.google.com/");
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNow(ERR_FAILED, nullptr);
 
   ASSERT_EQ(0u, factory->pending_requests().size());
   // As the proxy resolver factory failed the request and is configured for a
   // mandatory PAC script, ProxyService must not implicitly fall-back to DIRECT.
   EXPECT_EQ(ERR_MANDATORY_PROXY_CONFIGURATION_FAILED,
             callback1.WaitForResult());
   EXPECT_FALSE(info.is_direct());
 
   // As the proxy resolver factory failed the request and is configured for a
   // mandatory PAC script, ProxyService must not implicitly fall-back to DIRECT.
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback2.callback(), NULL,
-                            NULL, BoundNetLog());
+  rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                            callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_MANDATORY_PROXY_CONFIGURATION_FAILED, rv);
   EXPECT_FALSE(info.is_direct());
 }
 
 TEST_F(ProxyServiceTest, ProxyResolverFailsParsingJavaScriptMandatoryPac) {
   // Test what happens when the ProxyResolver fails that is configured to use a
   // mandatory PAC script. The download of the PAC script has already
   // succeeded but the PAC script contains no valid javascript.
 
   ProxyConfig config(
       ProxyConfig::CreateFromCustomPacURL(GURL("http://foopy/proxy.pac")));
   config.set_pac_mandatory(true);
 
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
 
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start resolve request.
   GURL url("http://www.google.com/");
   ProxyInfo info;
   TestCompletionCallback callback;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Check that nothing has been sent to the proxy resolver factory yet.
   ASSERT_EQ(0u, factory->pending_requests().size());
 
   // Downloading the PAC script succeeds.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
   fetcher->NotifyFetchCompletion(OK, "invalid-script-contents");
 
@@ skipping 18 matching lines @@
       ProxyConfig::CreateFromCustomPacURL(GURL("http://foopy/proxy.pac")));
   config.set_pac_mandatory(true);
 
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   // Start first resolve request.
   GURL url("http://www.google.com/");
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // Fail the first resolve request in MockAsyncProxyResolver.
   resolver.pending_jobs()[0]->CompleteNow(ERR_FAILED);
 
   // As the proxy resolver failed the request and is configured for a mandatory
   // PAC script, ProxyService must not implicitly fall-back to DIRECT.
   EXPECT_EQ(ERR_MANDATORY_PROXY_CONFIGURATION_FAILED,
             callback1.WaitForResult());
   EXPECT_FALSE(info.is_direct());
 
   // The second resolve request will try to run through the proxy resolver,
   // regardless of whether the first request failed in it.
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback2.callback(), NULL,
-                            NULL, BoundNetLog());
+  rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                            callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // This time we will have the resolver succeed (perhaps the PAC script has
   // a dependency on the current time).
   resolver.pending_jobs()[0]->results()->UseNamedProxy("foopy_valid:8080");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   EXPECT_EQ(OK, callback2.WaitForResult());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy_valid:8080", info.proxy_server().ToURI());
 }
 
 TEST_F(ProxyServiceTest, ProxyFallback) {
   // Test what happens when we specify multiple proxy servers and some of them
   // are bad.
 
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   // Get the proxy information.
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // Set the result in proxy resolver.
   resolver.pending_jobs()[0]->results()->UseNamedProxy(
       "foopy1:8080;foopy2:9090");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   // The first item is valid.
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
 
   EXPECT_FALSE(info.proxy_resolve_start_time().is_null());
   EXPECT_FALSE(info.proxy_resolve_end_time().is_null());
   EXPECT_LE(info.proxy_resolve_start_time(), info.proxy_resolve_end_time());
   base::TimeTicks proxy_resolve_start_time = info.proxy_resolve_start_time();
   base::TimeTicks proxy_resolve_end_time = info.proxy_resolve_end_time();
 
   // Fake an error on the proxy.
   TestCompletionCallback callback2;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback2.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback2.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
 
   // Proxy times should not have been modified by fallback.
   EXPECT_EQ(proxy_resolve_start_time, info.proxy_resolve_start_time());
   EXPECT_EQ(proxy_resolve_end_time, info.proxy_resolve_end_time());
 
   // The second proxy should be specified.
   EXPECT_EQ("foopy2:9090", info.proxy_server().ToURI());
   // Report back that the second proxy worked.  This will globally mark the
   // first proxy as bad.
   TestProxyFallbackProxyDelegate test_delegate;
   service.ReportSuccess(info, &test_delegate);
   EXPECT_EQ("foopy1:8080", test_delegate.proxy_server().ToURI());
   EXPECT_EQ(ERR_PROXY_CONNECTION_FAILED,
             test_delegate.proxy_fallback_net_error());
 
   TestCompletionCallback callback3;
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback3.callback(), NULL,
-                            NULL, BoundNetLog());
+  rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                            callback3.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // Set the result in proxy resolver -- the second result is already known
   // to be bad, so we will not try to use it initially.
   resolver.pending_jobs()[0]->results()->UseNamedProxy(
       "foopy3:7070;foopy1:8080;foopy2:9090");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   EXPECT_EQ(OK, callback3.WaitForResult());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy3:7070", info.proxy_server().ToURI());
 
   // Proxy times should have been updated, so get them again.
   EXPECT_LE(proxy_resolve_end_time, info.proxy_resolve_start_time());
   EXPECT_FALSE(info.proxy_resolve_start_time().is_null());
   EXPECT_FALSE(info.proxy_resolve_end_time().is_null());
   EXPECT_LE(info.proxy_resolve_start_time(), info.proxy_resolve_end_time());
   proxy_resolve_start_time = info.proxy_resolve_start_time();
   proxy_resolve_end_time = info.proxy_resolve_end_time();
 
   // We fake another error. It should now try the third one.
   TestCompletionCallback callback4;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback4.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback4.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_EQ("foopy2:9090", info.proxy_server().ToURI());
 
   // We fake another error. At this point we have tried all of the
   // proxy servers we thought were valid; next we try the proxy server
   // that was in our bad proxies map (foopy1:8080).
   TestCompletionCallback callback5;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback5.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback5.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
 
   // Fake another error, the last proxy is gone, the list should now be empty,
   // so there is nothing left to try.
   TestCompletionCallback callback6;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback6.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback6.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_FAILED, rv);
   EXPECT_FALSE(info.is_direct());
   EXPECT_TRUE(info.is_empty());
 
   // Proxy times should not have been modified by fallback.
   EXPECT_EQ(proxy_resolve_start_time, info.proxy_resolve_start_time());
   EXPECT_EQ(proxy_resolve_end_time, info.proxy_resolve_end_time());
 
   // Look up proxies again
   TestCompletionCallback callback7;
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback7.callback(), NULL,
-                            NULL, BoundNetLog());
+  rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                            callback7.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // This time, the first 3 results have been found to be bad, but only the
   // first proxy has been confirmed ...
   resolver.pending_jobs()[0]->results()->UseNamedProxy(
       "foopy1:8080;foopy3:7070;foopy2:9090;foopy4:9091");
   resolver.pending_jobs()[0]->CompleteNow(OK);
@@ skipping 13 matching lines @@
 // fallback choice to DIRECT.
 TEST_F(ProxyServiceTest, ProxyFallbackToDirect) {
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   // Get the proxy information.
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // Set the result in proxy resolver.
   resolver.pending_jobs()[0]->results()->UsePacString(
       "PROXY foopy1:8080; PROXY foopy2:9090; DIRECT");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   // Get the first result.
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
 
   // Fake an error on the proxy.
   TestCompletionCallback callback2;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback2.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback2.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
 
   // Now we get back the second proxy.
   EXPECT_EQ("foopy2:9090", info.proxy_server().ToURI());
 
   // Fake an error on this proxy as well.
   TestCompletionCallback callback3;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback3.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback3.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
 
   // Finally, we get back DIRECT.
   EXPECT_TRUE(info.is_direct());
 
   EXPECT_FALSE(info.proxy_resolve_start_time().is_null());
   EXPECT_FALSE(info.proxy_resolve_end_time().is_null());
   EXPECT_LE(info.proxy_resolve_start_time(), info.proxy_resolve_end_time());
 
   // Now we tell the proxy service that even DIRECT failed.
   TestCompletionCallback callback4;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback4.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback4.callback(), nullptr, nullptr, BoundNetLog());
   // There was nothing left to try after DIRECT, so we are out of
   // choices.
   EXPECT_EQ(ERR_FAILED, rv);
 }
 
 TEST_F(ProxyServiceTest, ProxyFallback_NewSettings) {
   // Test proxy failover when new settings are available.
 
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   // Get the proxy information.
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // Set the result in proxy resolver.
   resolver.pending_jobs()[0]->results()->UseNamedProxy(
       "foopy1:8080;foopy2:9090");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   // The first item is valid.
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
 
   // Fake an error on the proxy, and also a new configuration on the proxy.
   config_service->SetConfig(
       ProxyConfig::CreateFromCustomPacURL(GURL("http://foopy-new/proxy.pac")));
 
   TestCompletionCallback callback2;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback2.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback2.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy-new/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   resolver.pending_jobs()[0]->results()->UseNamedProxy(
       "foopy1:8080;foopy2:9090");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   // The first proxy is still there since the configuration changed.
   EXPECT_EQ(OK, callback2.WaitForResult());
   EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
 
   // We fake another error. It should now ignore the first one.
   TestCompletionCallback callback3;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback3.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback3.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_EQ("foopy2:9090", info.proxy_server().ToURI());
 
   // We simulate a new configuration.
   config_service->SetConfig(
       ProxyConfig::CreateFromCustomPacURL(
           GURL("http://foopy-new2/proxy.pac")));
 
   // We fake another error. It should go back to the first proxy.
   TestCompletionCallback callback4;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback4.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback4.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy-new2/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   resolver.pending_jobs()[0]->results()->UseNamedProxy(
@@ skipping 12 matching lines @@
   // Test proxy failover when the configuration is bad.
 
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   // Get the proxy information.
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   resolver.pending_jobs()[0]->results()->UseNamedProxy(
       "foopy1:8080;foopy2:9090");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   // The first item is valid.
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
 
   // Fake a proxy error.
   TestCompletionCallback callback2;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback2.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback2.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
 
   // The first proxy is ignored, and the second one is selected.
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy2:9090", info.proxy_server().ToURI());
 
   // Fake a PAC failure.
   ProxyInfo info2;
   TestCompletionCallback callback3;
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info2, callback3.callback(),
-                            NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info2,
+                            callback3.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // This simulates a javascript runtime error in the PAC script.
   resolver.pending_jobs()[0]->CompleteNow(ERR_FAILED);
 
   // Although the resolver failed, the ProxyService will implicitly fall-back
   // to a DIRECT connection.
   EXPECT_EQ(OK, callback3.WaitForResult());
   EXPECT_TRUE(info2.is_direct());
   EXPECT_FALSE(info2.is_empty());
 
   // The PAC script will work properly next time and successfully return a
   // proxy list. Since we have not marked the configuration as bad, it should
   // "just work" the next time we call it.
   ProxyInfo info3;
   TestCompletionCallback callback4;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info3,
-      callback4.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info3,
+      callback4.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   resolver.pending_jobs()[0]->results()->UseNamedProxy(
       "foopy1:8080;foopy2:9090");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   // The first proxy is not there since the it was added to the bad proxies
@@ skipping 14 matching lines @@
       ProxyConfig::CreateFromCustomPacURL(GURL("http://foopy/proxy.pac")));
 
   config.set_pac_mandatory(true);
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   // Get the proxy information.
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   resolver.pending_jobs()[0]->results()->UseNamedProxy(
       "foopy1:8080;foopy2:9090");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   // The first item is valid.
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
 
   // Fake a proxy error.
   TestCompletionCallback callback2;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
-      callback2.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info,
+      callback2.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
 
   // The first proxy is ignored, and the second one is selected.
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy2:9090", info.proxy_server().ToURI());
 
   // Fake a PAC failure.
   ProxyInfo info2;
   TestCompletionCallback callback3;
-  rv = service.ResolveProxy(url, LOAD_NORMAL, &info2, callback3.callback(),
-                            NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info2,
+                            callback3.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   // This simulates a javascript runtime error in the PAC script.
   resolver.pending_jobs()[0]->CompleteNow(ERR_FAILED);
 
   // Although the resolver failed, the ProxyService will NOT fall-back
   // to a DIRECT connection as it is configured as mandatory.
   EXPECT_EQ(ERR_MANDATORY_PROXY_CONFIGURATION_FAILED,
             callback3.WaitForResult());
   EXPECT_FALSE(info2.is_direct());
   EXPECT_TRUE(info2.is_empty());
 
   // The PAC script will work properly next time and successfully return a
   // proxy list. Since we have not marked the configuration as bad, it should
   // "just work" the next time we call it.
   ProxyInfo info3;
   TestCompletionCallback callback4;
   rv = service.ReconsiderProxyAfterError(
-      url, LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info3,
-      callback4.callback(), NULL, NULL, BoundNetLog());
+      url, std::string(), LOAD_NORMAL, ERR_PROXY_CONNECTION_FAILED, &info3,
+      callback4.callback(), nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(url, resolver.pending_jobs()[0]->url());
 
   resolver.pending_jobs()[0]->results()->UseNamedProxy(
       "foopy1:8080;foopy2:9090");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   // The first proxy is not there since the it was added to the bad proxies
   // list by the earlier ReconsiderProxyAfterError().
   EXPECT_EQ(OK, callback4.WaitForResult());
   EXPECT_FALSE(info3.is_direct());
   EXPECT_EQ("foopy1:8080", info3.proxy_server().ToURI());
 }
 
 TEST_F(ProxyServiceTest, ProxyBypassList) {
   // Test that the proxy bypass rules are consulted.
 
   TestCompletionCallback callback[2];
   ProxyInfo info[2];
   ProxyConfig config;
   config.proxy_rules().ParseFromString("foopy1:8080;foopy2:9090");
   config.set_auto_detect(false);
   config.proxy_rules().bypass_rules.ParseFromString("*.org");
 
   ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                       nullptr, NULL);
+                       nullptr, nullptr);
 
   int rv;
   GURL url1("http://www.webkit.org");
   GURL url2("http://www.webkit.com");
 
   // Request for a .org domain should bypass proxy.
-  rv = service.ResolveProxy(url1, LOAD_NORMAL, &info[0], callback[0].callback(),
-                            NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url1, std::string(), LOAD_NORMAL, &info[0],
+                            callback[0].callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_TRUE(info[0].is_direct());
 
   // Request for a .com domain hits the proxy.
-  rv = service.ResolveProxy(url2, LOAD_NORMAL, &info[1], callback[1].callback(),
-                            NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url2, std::string(), LOAD_NORMAL, &info[1],
+                            callback[1].callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_EQ("foopy1:8080", info[1].proxy_server().ToURI());
 }
 
 TEST_F(ProxyServiceTest, MarkProxiesAsBadTests) {
   ProxyConfig config;
   config.proxy_rules().ParseFromString(
       "http=foopy1:8080;http=foopy2:8080;http=foopy3.8080;http=foopy4:8080");
   config.set_auto_detect(false);
 
   ProxyList proxy_list;
   std::vector<ProxyServer> additional_bad_proxies;
   for (const ProxyServer& proxy_server :
        config.proxy_rules().proxies_for_http.GetAll()) {
     proxy_list.AddProxyServer(proxy_server);
     if (proxy_server == config.proxy_rules().proxies_for_http.Get())
       continue;
 
     additional_bad_proxies.push_back(proxy_server);
   }
 
   EXPECT_EQ(3u, additional_bad_proxies.size());
 
   ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                       nullptr, NULL);
+                       nullptr, nullptr);
   ProxyInfo proxy_info;
   proxy_info.UseProxyList(proxy_list);
   const ProxyRetryInfoMap& retry_info = service.proxy_retry_info();
   service.MarkProxiesAsBadUntil(proxy_info, base::TimeDelta::FromSeconds(1),
                                 additional_bad_proxies, BoundNetLog());
   ASSERT_EQ(4u, retry_info.size());
   for (const ProxyServer& proxy_server :
        config.proxy_rules().proxies_for_http.GetAll()) {
     ProxyRetryInfoMap::const_iterator i =
         retry_info.find(proxy_server.host_port_pair().ToString());
     ASSERT_TRUE(i != retry_info.end());
   }
 }
 
 TEST_F(ProxyServiceTest, PerProtocolProxyTests) {
   ProxyConfig config;
   config.proxy_rules().ParseFromString("http=foopy1:8080;https=foopy2:8080");
   config.set_auto_detect(false);
   {
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("http://www.msn.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     EXPECT_EQ(OK, rv);
     EXPECT_FALSE(info.is_direct());
     EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
   }
   {
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("ftp://ftp.google.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     EXPECT_EQ(OK, rv);
     EXPECT_TRUE(info.is_direct());
     EXPECT_EQ("direct://", info.proxy_server().ToURI());
   }
   {
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("https://webbranch.techcu.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     EXPECT_EQ(OK, rv);
     EXPECT_FALSE(info.is_direct());
     EXPECT_EQ("foopy2:8080", info.proxy_server().ToURI());
   }
   {
     config.proxy_rules().ParseFromString("foopy1:8080");
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("http://www.microsoft.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     EXPECT_EQ(OK, rv);
     EXPECT_FALSE(info.is_direct());
     EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
   }
 }
 
 TEST_F(ProxyServiceTest, ProxyConfigSourcePropagates) {
   // Test that the proxy config source is set correctly when resolving proxies
   // using manual proxy rules. Namely, the config source should only be set if
   // any of the rules were applied.
   {
     ProxyConfig config;
     config.set_source(PROXY_CONFIG_SOURCE_TEST);
     config.proxy_rules().ParseFromString("https=foopy2:8080");
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("http://www.google.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     ASSERT_EQ(OK, rv);
     // Should be SOURCE_TEST, even if there are no HTTP proxies configured.
     EXPECT_EQ(PROXY_CONFIG_SOURCE_TEST, info.config_source());
   }
   {
     ProxyConfig config;
     config.set_source(PROXY_CONFIG_SOURCE_TEST);
     config.proxy_rules().ParseFromString("https=foopy2:8080");
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("https://www.google.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     ASSERT_EQ(OK, rv);
     // Used the HTTPS proxy. So source should be TEST.
     EXPECT_EQ(PROXY_CONFIG_SOURCE_TEST, info.config_source());
   }
   {
     ProxyConfig config;
     config.set_source(PROXY_CONFIG_SOURCE_TEST);
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("http://www.google.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     ASSERT_EQ(OK, rv);
     // ProxyConfig is empty. Source should still be TEST.
     EXPECT_EQ(PROXY_CONFIG_SOURCE_TEST, info.config_source());
   }
 }
 
 // If only HTTP and a SOCKS proxy are specified, check if ftp/https queries
 // fall back to the SOCKS proxy.
 TEST_F(ProxyServiceTest, DefaultProxyFallbackToSOCKS) {
   ProxyConfig config;
   config.proxy_rules().ParseFromString("http=foopy1:8080;socks=foopy2:1080");
   config.set_auto_detect(false);
   EXPECT_EQ(ProxyConfig::ProxyRules::TYPE_PROXY_PER_SCHEME,
             config.proxy_rules().type);
 
   {
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("http://www.msn.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     EXPECT_EQ(OK, rv);
     EXPECT_FALSE(info.is_direct());
     EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
   }
   {
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("ftp://ftp.google.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     EXPECT_EQ(OK, rv);
     EXPECT_FALSE(info.is_direct());
     EXPECT_EQ("socks4://foopy2:1080", info.proxy_server().ToURI());
   }
   {
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("https://webbranch.techcu.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     EXPECT_EQ(OK, rv);
     EXPECT_FALSE(info.is_direct());
     EXPECT_EQ("socks4://foopy2:1080", info.proxy_server().ToURI());
   }
   {
     ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                         nullptr, NULL);
+                         nullptr, nullptr);
     GURL test_url("unknown://www.microsoft.com");
     ProxyInfo info;
     TestCompletionCallback callback;
-    int rv =
-        service.ResolveProxy(test_url, LOAD_NORMAL, &info, callback.callback(),
-                             NULL, NULL, BoundNetLog());
+    int rv = service.ResolveProxy(test_url, std::string(), LOAD_NORMAL, &info,
+                                  callback.callback(), nullptr, nullptr,
+                                  BoundNetLog());
     EXPECT_EQ(OK, rv);
     EXPECT_FALSE(info.is_direct());
     EXPECT_EQ("socks4://foopy2:1080", info.proxy_server().ToURI());
   }
 }
 
 // Test cancellation of an in-progress request.
 TEST_F(ProxyServiceTest, CancelInProgressRequest) {
   const GURL url1("http://request1");
   const GURL url2("http://request2");
   const GURL url3("http://request3");
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   // Start 3 requests.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url1, LOAD_NORMAL, &info1, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url1, std::string(), LOAD_NORMAL, &info1,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Successfully initialize the PAC script.
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   GetPendingJobsForURLs(resolver, url1);
 
   ProxyInfo info2;
   TestCompletionCallback callback2;
   ProxyService::PacRequest* request2;
-  rv = service.ResolveProxy(url2, LOAD_NORMAL, &info2, callback2.callback(),
-                            &request2, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url2, std::string(), LOAD_NORMAL, &info2,
+                            callback2.callback(), &request2, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   GetPendingJobsForURLs(resolver, url1, url2);
 
   ProxyInfo info3;
   TestCompletionCallback callback3;
-  rv = service.ResolveProxy(url3, LOAD_NORMAL, &info3, callback3.callback(),
-                            NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url3, std::string(), LOAD_NORMAL, &info3,
+                            callback3.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
   GetPendingJobsForURLs(resolver, url1, url2, url3);
 
   // Cancel the second request
   service.CancelPacRequest(request2);
 
   JobMap jobs = GetPendingJobsForURLs(resolver, url1, url3);
 
   // Complete the two un-cancelled jobs.
   // We complete the last one first, just to mix it up a bit.
@@ skipping 20 matching lines @@
   const GURL url2("http://request2");
   const GURL url3("http://request3");
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 3 requests.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
   ProxyService::PacRequest* request1;
-  int rv = service.ResolveProxy(url1, LOAD_NORMAL, &info1, callback1.callback(),
-                                &request1, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url1, std::string(), LOAD_NORMAL, &info1,
+                                callback1.callback(), &request1, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // The first request should have triggered download of PAC script.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   ProxyInfo info2;
   TestCompletionCallback callback2;
   ProxyService::PacRequest* request2;
-  rv = service.ResolveProxy(url2, LOAD_NORMAL, &info2, callback2.callback(),
-                            &request2, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url2, std::string(), LOAD_NORMAL, &info2,
+                            callback2.callback(), &request2, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ProxyInfo info3;
   TestCompletionCallback callback3;
   ProxyService::PacRequest* request3;
-  rv = service.ResolveProxy(url3, LOAD_NORMAL, &info3, callback3.callback(),
-                            &request3, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url3, std::string(), LOAD_NORMAL, &info3,
+                            callback3.callback(), &request3, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Nothing has been sent to the factory yet.
   EXPECT_TRUE(factory->pending_requests().empty());
 
   EXPECT_EQ(LOAD_STATE_DOWNLOADING_PROXY_SCRIPT,
             service.GetLoadState(request1));
   EXPECT_EQ(LOAD_STATE_DOWNLOADING_PROXY_SCRIPT,
             service.GetLoadState(request2));
   EXPECT_EQ(LOAD_STATE_DOWNLOADING_PROXY_SCRIPT,
@@ skipping 52 matching lines @@
   const GURL url1("http://request1");
   const GURL url2("http://request2");
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 2 jobs.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url1, LOAD_NORMAL, &info1, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url1, std::string(), LOAD_NORMAL, &info1,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // The first request should have triggered download of PAC script.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   ProxyInfo info2;
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(url2, LOAD_NORMAL, &info2, callback2.callback(),
-                            NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url2, std::string(), LOAD_NORMAL, &info2,
+                            callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // At this point the ProxyService should be waiting for the
   // ProxyScriptFetcher to invoke its completion callback, notifying it of
   // PAC script download completion.
 
   // We now change out the ProxyService's script fetcher. We should restart
   // the initialization with the new fetcher.
 
   fetcher = new MockProxyScriptFetcher;
@@ skipping 17 matching lines @@
 // Test cancellation of a request, while the PAC script is being fetched.
 TEST_F(ProxyServiceTest, CancelWhilePACFetching) {
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 3 requests.
   ProxyInfo info1;
   TestCompletionCallback callback1;
   ProxyService::PacRequest* request1;
   BoundTestNetLog log1;
-  int rv =
-      service.ResolveProxy(GURL("http://request1"), LOAD_NORMAL, &info1,
-                           callback1.callback(), &request1, NULL, log1.bound());
+  int rv = service.ResolveProxy(GURL("http://request1"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                &request1, nullptr, log1.bound());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // The first request should have triggered download of PAC script.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   ProxyInfo info2;
   TestCompletionCallback callback2;
   ProxyService::PacRequest* request2;
-  rv = service.ResolveProxy(GURL("http://request2"), LOAD_NORMAL, &info2,
-                            callback2.callback(), &request2, NULL,
+  rv = service.ResolveProxy(GURL("http://request2"), std::string(), LOAD_NORMAL,
+                            &info2, callback2.callback(), &request2, nullptr,
                             BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ProxyInfo info3;
   TestCompletionCallback callback3;
-  rv = service.ResolveProxy(GURL("http://request3"), LOAD_NORMAL, &info3,
-                            callback3.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://request3"), std::string(), LOAD_NORMAL,
+                            &info3, callback3.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Nothing has been sent to the factory yet.
   EXPECT_TRUE(factory->pending_requests().empty());
 
   // Cancel the first 2 jobs.
   service.CancelPacRequest(request1);
   service.CancelPacRequest(request2);
 
   // At this point the ProxyService should be waiting for the
@@ skipping 46 matching lines @@
   ProxyConfig config;
   config.set_auto_detect(true);
   config.set_pac_url(GURL("http://foopy/proxy.pac"));
   config.proxy_rules().ParseFromString("http=foopy:80");  // Won't be used.
 
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 2 requests.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url1, LOAD_NORMAL, &info1, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url1, std::string(), LOAD_NORMAL, &info1,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ProxyInfo info2;
   TestCompletionCallback callback2;
   ProxyService::PacRequest* request2;
-  rv = service.ResolveProxy(url2, LOAD_NORMAL, &info2, callback2.callback(),
-                            &request2, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url2, std::string(), LOAD_NORMAL, &info2,
+                            callback2.callback(), &request2, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Check that nothing has been sent to the proxy resolver factory yet.
   ASSERT_EQ(0u, factory->pending_requests().size());
 
   // It should be trying to auto-detect first -- FAIL the autodetect during
   // the script download.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://wpad/wpad.dat"), fetcher->pending_request_url());
   fetcher->NotifyFetchCompletion(ERR_FAILED, std::string());
@@ skipping 40 matching lines @@
   ProxyConfig config;
   config.set_auto_detect(true);
   config.set_pac_url(GURL("http://foopy/proxy.pac"));
   config.proxy_rules().ParseFromString("http=foopy:80");  // Won't be used.
 
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 2 requests.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv = service.ResolveProxy(url1, LOAD_NORMAL, &info1, callback1.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url1, std::string(), LOAD_NORMAL, &info1,
+                                callback1.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ProxyInfo info2;
   TestCompletionCallback callback2;
   ProxyService::PacRequest* request2;
-  rv = service.ResolveProxy(url2, LOAD_NORMAL, &info2, callback2.callback(),
-                            &request2, NULL, BoundNetLog());
+  rv = service.ResolveProxy(url2, std::string(), LOAD_NORMAL, &info2,
+                            callback2.callback(), &request2, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Check that nothing has been sent to the proxy resolver factory yet.
   ASSERT_EQ(0u, factory->pending_requests().size());
 
   // It should be trying to auto-detect first -- succeed the download.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://wpad/wpad.dat"), fetcher->pending_request_url());
   fetcher->NotifyFetchCompletion(OK, "invalid-script-contents");
 
@@ skipping 33 matching lines @@
 TEST_F(ProxyServiceTest, FallbackFromAutodetectToCustomToManual) {
   ProxyConfig config;
   config.set_auto_detect(true);
   config.set_pac_url(GURL("http://foopy/proxy.pac"));
   config.proxy_rules().ParseFromString("http=foopy:80");
 
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 2 jobs.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://request1"), LOAD_NORMAL, &info1,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://request1"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ProxyInfo info2;
   TestCompletionCallback callback2;
   ProxyService::PacRequest* request2;
-  rv = service.ResolveProxy(GURL("http://request2"), LOAD_NORMAL, &info2,
-                            callback2.callback(), &request2, NULL,
+  rv = service.ResolveProxy(GURL("http://request2"), std::string(), LOAD_NORMAL,
+                            &info2, callback2.callback(), &request2, nullptr,
                             BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Check that nothing has been sent to the proxy resolver factory yet.
   ASSERT_EQ(0u, factory->pending_requests().size());
 
   // It should be trying to auto-detect first -- fail the download.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://wpad/wpad.dat"), fetcher->pending_request_url());
   fetcher->NotifyFetchCompletion(ERR_FAILED, std::string());
@@ skipping 22 matching lines @@
   config.set_auto_detect(true);
   config.set_pac_url(GURL("http://foopy/proxy.pac"));
   config.proxy_rules().ParseFromString("http=foopy:80");  // Not used.
   config.proxy_rules().bypass_rules.ParseFromString("www.google.com");
 
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 1 requests.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://www.google.com"), LOAD_NORMAL, &info1,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://www.google.com"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Check that nothing has been sent to the proxy resolver factory yet.
   ASSERT_EQ(0u, factory->pending_requests().size());
 
   // It should be trying to auto-detect first -- succeed the download.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://wpad/wpad.dat"), fetcher->pending_request_url());
   fetcher->NotifyFetchCompletion(OK, kValidPacScript1);
 
   EXPECT_EQ(ASCIIToUTF16(kValidPacScript1),
             factory->pending_requests()[0]->script_data()->utf16());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(GURL("http://www.google.com"), resolver.pending_jobs()[0]->url());
 
   // Complete the pending request.
   resolver.pending_jobs()[0]->results()->UseNamedProxy("request1:80");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   // Verify that request ran as expected.
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_EQ("request1:80", info1.proxy_server().ToURI());
 
   // Start another request, it should pickup the bypass item.
   ProxyInfo info2;
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(GURL("http://www.google.com"), LOAD_NORMAL, &info2,
-                            callback2.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://www.google.com"), std::string(),
+                            LOAD_NORMAL, &info2, callback2.callback(), nullptr,
+                            nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(GURL("http://www.google.com"), resolver.pending_jobs()[0]->url());
 
   // Complete the pending request.
   resolver.pending_jobs()[0]->results()->UseNamedProxy("request2:80");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   EXPECT_EQ(OK, callback2.WaitForResult());
   EXPECT_EQ("request2:80", info2.proxy_server().ToURI());
 }
 
 // Delete the ProxyService while InitProxyResolver has an outstanding
 // request to the script fetcher. When run under valgrind, should not
 // have any memory errors (used to be that the ProxyScriptFetcher was
 // being deleted prior to the InitProxyResolver).
 TEST_F(ProxyServiceTest, DeleteWhileInitProxyResolverHasOutstandingFetch) {
   ProxyConfig config =
     ProxyConfig::CreateFromCustomPacURL(GURL("http://foopy/proxy.pac"));
 
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 1 request.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://www.google.com"), LOAD_NORMAL, &info1,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://www.google.com"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Check that nothing has been sent to the proxy resolver factory yet.
   ASSERT_EQ(0u, factory->pending_requests().size());
 
   // InitProxyResolver should have issued a request to the ProxyScriptFetcher
   // and be waiting on that to complete.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 }
 
 // Delete the ProxyService while InitProxyResolver has an outstanding
 // request to the proxy resolver. When run under valgrind, should not
 // have any memory errors (used to be that the ProxyResolver was
 // being deleted prior to the InitProxyResolver).
 TEST_F(ProxyServiceTest, DeleteWhileInitProxyResolverHasOutstandingSet) {
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   ProxyInfo info;
   TestCompletionCallback callback;
-  int rv = service.ResolveProxy(url, LOAD_NORMAL, &info, callback.callback(),
-                                NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(url, std::string(), LOAD_NORMAL, &info,
+                                callback.callback(), nullptr, nullptr,
+                                BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   EXPECT_EQ(GURL("http://foopy/proxy.pac"),
             factory->pending_requests()[0]->script_data()->url());
 }
 
 TEST_F(ProxyServiceTest, ResetProxyConfigService) {
   ProxyConfig config1;
   config1.proxy_rules().ParseFromString("foopy1:8080");
   config1.set_auto_detect(false);
   ProxyService service(make_scoped_ptr(new MockProxyConfigService(config1)),
-                       nullptr, NULL);
+                       nullptr, nullptr);
 
   ProxyInfo info;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://request1"), LOAD_NORMAL, &info,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://request1"), std::string(),
+                                LOAD_NORMAL, &info, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_EQ("foopy1:8080", info.proxy_server().ToURI());
 
   ProxyConfig config2;
   config2.proxy_rules().ParseFromString("foopy2:8080");
   config2.set_auto_detect(false);
   service.ResetConfigService(
       make_scoped_ptr(new MockProxyConfigService(config2)));
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(GURL("http://request2"), LOAD_NORMAL, &info,
-                            callback2.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://request2"), std::string(), LOAD_NORMAL,
+                            &info, callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_EQ("foopy2:8080", info.proxy_server().ToURI());
 }
 
 // Test that when going from a configuration that required PAC to one
 // that does NOT, we unset the variable |should_use_proxy_resolver_|.
 TEST_F(ProxyServiceTest, UpdateConfigFromPACToDirect) {
   ProxyConfig config = ProxyConfig::CreateAutoDetect();
 
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   // Start 1 request.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://www.google.com"), LOAD_NORMAL, &info1,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://www.google.com"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Successfully set the autodetect script.
   EXPECT_EQ(ProxyResolverScriptData::TYPE_AUTO_DETECT,
             factory->pending_requests()[0]->script_data()->type());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   // Complete the pending request.
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   resolver.pending_jobs()[0]->results()->UseNamedProxy("request1:80");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   // Verify that request ran as expected.
   EXPECT_EQ(OK, callback1.WaitForResult());
   EXPECT_EQ("request1:80", info1.proxy_server().ToURI());
 
   // Force the ProxyService to pull down a new proxy configuration.
   // (Even though the configuration isn't old/bad).
   //
   // This new configuration no longer has auto_detect set, so
   // jobs should complete synchronously now as direct-connect.
   config_service->SetConfig(ProxyConfig::CreateDirect());
 
   // Start another request -- the effective configuration has changed.
   ProxyInfo info2;
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(GURL("http://www.google.com"), LOAD_NORMAL, &info2,
-                            callback2.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://www.google.com"), std::string(),
+                            LOAD_NORMAL, &info2, callback2.callback(), nullptr,
+                            nullptr, BoundNetLog());
   EXPECT_EQ(OK, rv);
 
   EXPECT_TRUE(info2.is_direct());
 }
 
 TEST_F(ProxyServiceTest, NetworkChangeTriggersPacRefetch) {
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
@@ skipping 10 matching lines @@
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Disable the "wait after IP address changes" hack, so this unit-test can
   // complete quickly.
   service.set_stall_proxy_auto_config_delay(base::TimeDelta());
 
   // Start 1 request.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://request1"), LOAD_NORMAL, &info1,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://request1"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // The first request should have triggered initial download of PAC script.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   // Nothing has been sent to the factory yet.
   EXPECT_TRUE(factory->pending_requests().empty());
 
   // At this point the ProxyService should be waiting for the
@@ skipping 20 matching lines @@
 
   // Now simluate a change in the network. The ProxyConfigService is still
   // going to return the same PAC URL as before, but this URL needs to be
   // refetched on the new network.
   NetworkChangeNotifier::NotifyObserversOfIPAddressChangeForTests();
   base::MessageLoop::current()->RunUntilIdle();  // Notification happens async.
 
   // Start a second request.
   ProxyInfo info2;
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(GURL("http://request2"), LOAD_NORMAL, &info2,
-                            callback2.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://request2"), std::string(), LOAD_NORMAL,
+                            &info2, callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // This second request should have triggered the re-download of the PAC
   // script (since we marked the network as having changed).
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   // Nothing has been sent to the factory yet.
   EXPECT_TRUE(factory->pending_requests().empty());
 
@@ skipping 42 matching lines @@
   ProxyService::set_pac_script_poll_policy(&poll_policy);
 
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 1 request.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://request1"), LOAD_NORMAL, &info1,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://request1"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // The first request should have triggered initial download of PAC script.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   // Nothing has been sent to the factory yet.
   EXPECT_TRUE(factory->pending_requests().empty());
 
   // At this point the ProxyService should be waiting for the
@@ skipping 38 matching lines @@
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   // At this point the ProxyService should have re-configured itself to use the
   // PAC script (thereby recovering from the initial fetch failure). We will
   // verify that the next Resolve request uses the resolver rather than
   // DIRECT.
 
   // Start a second request.
   ProxyInfo info2;
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(GURL("http://request2"), LOAD_NORMAL, &info2,
-                            callback2.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://request2"), std::string(), LOAD_NORMAL,
+                            &info2, callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Check that it was sent to the resolver.
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(GURL("http://request2"), resolver.pending_jobs()[0]->url());
 
   // Complete the pending second request.
   resolver.pending_jobs()[0]->results()->UseNamedProxy("request2:80");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
@@ skipping 13 matching lines @@
   ProxyService::set_pac_script_poll_policy(&poll_policy);
 
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 1 request.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://request1"), LOAD_NORMAL, &info1,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://request1"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // The first request should have triggered initial download of PAC script.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   // Nothing has been sent to the factory yet.
   EXPECT_TRUE(factory->pending_requests().empty());
 
   // At this point the ProxyService should be waiting for the
@@ skipping 44 matching lines @@
   EXPECT_EQ(ASCIIToUTF16(kValidPacScript2),
             factory->pending_requests()[0]->script_data()->utf16());
   factory->pending_requests()[0]->CompleteNowWithForwarder(OK, &resolver);
 
   // At this point the ProxyService should have re-configured itself to use the
   // new PAC script.
 
   // Start a second request.
   ProxyInfo info2;
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(GURL("http://request2"), LOAD_NORMAL, &info2,
-                            callback2.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://request2"), std::string(), LOAD_NORMAL,
+                            &info2, callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Check that it was sent to the resolver.
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(GURL("http://request2"), resolver.pending_jobs()[0]->url());
 
   // Complete the pending second request.
   resolver.pending_jobs()[0]->results()->UseNamedProxy("request2:80");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
@@ skipping 13 matching lines @@
   ProxyService::set_pac_script_poll_policy(&poll_policy);
 
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 1 request.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://request1"), LOAD_NORMAL, &info1,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://request1"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // The first request should have triggered initial download of PAC script.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   // Nothing has been sent to the factory yet.
   EXPECT_TRUE(factory->pending_requests().empty());
 
   // At this point the ProxyService should be waiting for the
@@ skipping 41 matching lines @@
 
   ASSERT_TRUE(factory->pending_requests().empty());
   ASSERT_TRUE(resolver.pending_jobs().empty());
 
   // At this point the ProxyService is still running the same PAC script as
   // before.
 
   // Start a second request.
   ProxyInfo info2;
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(GURL("http://request2"), LOAD_NORMAL, &info2,
-                            callback2.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://request2"), std::string(), LOAD_NORMAL,
+                            &info2, callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // Check that it was sent to the resolver.
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(GURL("http://request2"), resolver.pending_jobs()[0]->url());
 
   // Complete the pending second request.
   resolver.pending_jobs()[0]->results()->UseNamedProxy("request2:80");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
@@ skipping 13 matching lines @@
   ProxyService::set_pac_script_poll_policy(&poll_policy);
 
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 1 request.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://request1"), LOAD_NORMAL, &info1,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://request1"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // The first request should have triggered initial download of PAC script.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   // Nothing has been sent to the factory yet.
   EXPECT_TRUE(factory->pending_requests().empty());
 
   // At this point the ProxyService should be waiting for the
@@ skipping 38 matching lines @@
   fetcher->NotifyFetchCompletion(ERR_FAILED, std::string());
 
   base::MessageLoop::current()->RunUntilIdle();
 
   // At this point the ProxyService should have re-configured itself to use
   // DIRECT connections rather than the given proxy resolver.
 
   // Start a second request.
   ProxyInfo info2;
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(GURL("http://request2"), LOAD_NORMAL, &info2,
-                            callback2.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://request2"), std::string(), LOAD_NORMAL,
+                            &info2, callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_TRUE(info2.is_direct());
 }
 
 // Tests that the code which decides at what times to poll the PAC
 // script follows the expected policy.
 TEST_F(ProxyServiceTest, PACScriptPollingPolicy) {
   // Retrieve the internal polling policy implementation used by ProxyService.
   scoped_ptr<ProxyService::PacPollPolicy> policy =
       ProxyService::CreateDefaultPacPollPolicy();
@@ skipping 61 matching lines @@
   ProxyService::set_pac_script_poll_policy(&poll_policy);
 
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolver resolver;
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(true);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service.SetProxyScriptFetchers(
       fetcher, make_scoped_ptr(new DoNothingDhcpProxyScriptFetcher()));
 
   // Start 1 request.
 
   ProxyInfo info1;
   TestCompletionCallback callback1;
-  int rv =
-      service.ResolveProxy(GURL("http://request1"), LOAD_NORMAL, &info1,
-                           callback1.callback(), NULL, NULL, BoundNetLog());
+  int rv = service.ResolveProxy(GURL("http://request1"), std::string(),
+                                LOAD_NORMAL, &info1, callback1.callback(),
+                                nullptr, nullptr, BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // The first request should have triggered initial download of PAC script.
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   // Nothing has been sent to the factory yet.
   EXPECT_TRUE(factory->pending_requests().empty());
 
   // At this point the ProxyService should be waiting for the
@@ skipping 22 matching lines @@
   // Our PAC poller is set to update ONLY in response to network activity,
   // (i.e. another call to ResolveProxy()).
 
   ASSERT_FALSE(fetcher->has_pending_request());
   ASSERT_TRUE(factory->pending_requests().empty());
   ASSERT_TRUE(resolver.pending_jobs().empty());
 
   // Start a second request.
   ProxyInfo info2;
   TestCompletionCallback callback2;
-  rv = service.ResolveProxy(GURL("http://request2"), LOAD_NORMAL, &info2,
-                            callback2.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://request2"), std::string(), LOAD_NORMAL,
+                            &info2, callback2.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
 
   // This request should have sent work to the resolver; complete it.
   ASSERT_EQ(1u, resolver.pending_jobs().size());
   EXPECT_EQ(GURL("http://request2"), resolver.pending_jobs()[0]->url());
   resolver.pending_jobs()[0]->results()->UseNamedProxy("request2:80");
   resolver.pending_jobs()[0]->CompleteNow(OK);
 
   EXPECT_EQ(OK, callback2.WaitForResult());
   EXPECT_EQ("request2:80", info2.proxy_server().ToURI());
 
   // In response to getting that resolve request, the poller should have
   // started the next poll, and made it as far as to request the download.
 
   EXPECT_TRUE(fetcher->has_pending_request());
   EXPECT_EQ(GURL("http://foopy/proxy.pac"), fetcher->pending_request_url());
 
   // This time we will fail the download, to simulate a PAC script change.
   fetcher->NotifyFetchCompletion(ERR_FAILED, std::string());
 
   // Drain the message loop, so ProxyService is notified of the change
   // and has a chance to re-configure itself.
   base::MessageLoop::current()->RunUntilIdle();
 
   // Start a third request -- this time we expect to get a direct connection
   // since the PAC script poller experienced a failure.
   ProxyInfo info3;
   TestCompletionCallback callback3;
-  rv = service.ResolveProxy(GURL("http://request3"), LOAD_NORMAL, &info3,
-                            callback3.callback(), NULL, NULL, BoundNetLog());
+  rv = service.ResolveProxy(GURL("http://request3"), std::string(), LOAD_NORMAL,
+                            &info3, callback3.callback(), nullptr, nullptr,
+                            BoundNetLog());
   EXPECT_EQ(OK, rv);
   EXPECT_TRUE(info3.is_direct());
 }
 
 // Test that the synchronous resolution fails when a PAC script is active.
 TEST_F(ProxyServiceTest, SynchronousWithPAC) {
   MockProxyConfigService* config_service =
       new MockProxyConfigService("http://foopy/proxy.pac");
 
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(config_service),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   ProxyInfo info;
   info.UseDirect();
   BoundTestNetLog log;
 
   bool synchronous_success = service.TryResolveProxySynchronously(
-      url, LOAD_NORMAL, &info, NULL, log.bound());
+      url, std::string(), LOAD_NORMAL, &info, nullptr, log.bound());
   EXPECT_FALSE(synchronous_success);
 
   // |info| should not have been modified.
   EXPECT_TRUE(info.is_direct());
 }
 
 // Test that synchronous results are returned correctly if a fixed proxy
 // configuration is active.
 TEST_F(ProxyServiceTest, SynchronousWithFixedConfiguration) {
   ProxyConfig config;
   config.proxy_rules().ParseFromString("foopy1:8080");
   config.set_auto_detect(false);
 
   MockAsyncProxyResolverFactory* factory =
       new MockAsyncProxyResolverFactory(false);
 
   ProxyService service(make_scoped_ptr(new MockProxyConfigService(config)),
-                       make_scoped_ptr(factory), NULL);
+                       make_scoped_ptr(factory), nullptr);
 
   GURL url("http://www.google.com/");
 
   ProxyInfo info;
   BoundTestNetLog log;
 
   bool synchronous_success = service.TryResolveProxySynchronously(
-      url, LOAD_NORMAL, &info, NULL, log.bound());
+      url, std::string(), LOAD_NORMAL, &info, nullptr, log.bound());
   EXPECT_TRUE(synchronous_success);
   EXPECT_FALSE(info.is_direct());
   EXPECT_EQ("foopy1", info.proxy_server().host_port_pair().host());
 
   // No request should have been queued.
   EXPECT_EQ(0u, factory->pending_requests().size());
 }
 
 }  // namespace net