Race TCP connection to proxies with QUIC connections

net/http/http_stream_factory_impl_job_controller_unittest.cc

 // Copyright (c) 2016 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/http/http_stream_factory_impl_job_controller.h"
 
 #include <memory>
 
 #include "base/memory/ptr_util.h"
 #include "base/run_loop.h"
+#include "net/base/test_proxy_delegate.h"
 #include "net/dns/mock_host_resolver.h"
 #include "net/http/http_basic_stream.h"
 #include "net/http/http_stream_factory_impl_request.h"
 #include "net/http/http_stream_factory_test_util.h"
 #include "net/proxy/mock_proxy_resolver.h"
 #include "net/proxy/proxy_config_service_fixed.h"
 #include "net/proxy/proxy_info.h"
 #include "net/proxy/proxy_service.h"
 #include "net/quic/test_tools/quic_stream_factory_peer.h"
 #include "net/spdy/spdy_test_util_common.h"
+#include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gmock_mutant.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using ::testing::_;
 using ::testing::Invoke;
 
 namespace net {
 
 namespace {
 
@@ skipping 70 matching lines @@
 
 class HttpStreamFactoryImplJobControllerTest
     : public ::testing::Test,
       public ::testing::WithParamInterface<NextProto> {
  public:
   HttpStreamFactoryImplJobControllerTest()
       : session_deps_(ProxyService::CreateDirect()) {
     session_deps_.enable_quic = true;
   }
 
-  void Initialize() {
+  void Initialize(bool use_alternative_proxy) {
+    if (use_alternative_proxy) {
+      std::unique_ptr<ProxyService> proxy_service =
+          ProxyService::CreateFixedFromPacResult("HTTPS myproxy.org:443");
+      session_deps_.proxy_service.reset(proxy_service.release());
+
+      std::unique_ptr<TestProxyDelegate> test_proxy_delegate(
+          new TestProxyDelegate());
+      test_proxy_delegate_ = test_proxy_delegate.get();
+
+      test_proxy_delegate->set_alternative_proxy_server(
+          ProxyServer::FromPacString("QUIC myproxy.org:443"));
+      EXPECT_TRUE(test_proxy_delegate->alternative_proxy_server().is_quic());
+      session_deps_.proxy_delegate.reset(test_proxy_delegate.release());
+    }
     session_ = SpdySessionDependencies::SpdyCreateSession(&session_deps_);
     factory_ =
         static_cast<HttpStreamFactoryImpl*>(session_->http_stream_factory());
     job_controller_ = new HttpStreamFactoryImpl::JobController(
         factory_, &request_delegate_, session_.get(), &job_factory_);
     HttpStreamFactoryImplPeer::AddJobController(factory_, job_controller_);
   }
 
+  TestProxyDelegate* test_proxy_delegate() const {
+    return test_proxy_delegate_;
+  }
+
   ~HttpStreamFactoryImplJobControllerTest() {}
 
   void SetAlternativeService(const HttpRequestInfo& request_info,
                              AlternativeService alternative_service) {
     HostPortPair host_port_pair = HostPortPair::FromURL(request_info.url);
     url::SchemeHostPort server(request_info.url);
     base::Time expiration = base::Time::Now() + base::TimeDelta::FromDays(1);
     session_->http_server_properties()->SetAlternativeService(
         server, alternative_service, expiration);
   }
 
+  // Not owned by |this|.
+  TestProxyDelegate* test_proxy_delegate_;
   TestJobFactory job_factory_;
   MockHttpStreamRequestDelegate request_delegate_;
   SpdySessionDependencies session_deps_;
   std::unique_ptr<HttpNetworkSession> session_;
   HttpStreamFactoryImpl* factory_;
   HttpStreamFactoryImpl::JobController* job_controller_;
   std::unique_ptr<HttpStreamFactoryImpl::Request> request_;
 
   DISALLOW_COPY_AND_ASSIGN(HttpStreamFactoryImplJobControllerTest);
 };
 
 TEST_F(HttpStreamFactoryImplJobControllerTest,
        OnStreamFailedWithNoAlternativeJob) {
   ProxyConfig proxy_config;
   proxy_config.set_auto_detect(true);
   // Use asynchronous proxy resolver.
   MockAsyncProxyResolverFactory* proxy_resolver_factory =
       new MockAsyncProxyResolverFactory(false);
   session_deps_.proxy_service.reset(new ProxyService(
       base::WrapUnique(new ProxyConfigServiceFixed(proxy_config)),
       base::WrapUnique(proxy_resolver_factory), nullptr));
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("http://www.google.com");
 
   request_.reset(
       job_controller_->Start(request_info, &request_delegate_, nullptr,
                              BoundNetLog(), HttpStreamRequest::HTTP_STREAM,
                              DEFAULT_PRIORITY, SSLConfig(), SSLConfig()));
 
   EXPECT_TRUE(job_controller_->main_job());
 
   // There's no other alternative job. Thus when stream failed, it should
   // notify Request of the stream failure.
   EXPECT_CALL(request_delegate_, OnStreamFailed(ERR_FAILED, _)).Times(1);
   job_controller_->OnStreamFailed(job_factory_.main_job(), ERR_FAILED,
                                   SSLConfig());
 }
 
 TEST_F(HttpStreamFactoryImplJobControllerTest,
        OnStreamReadyWithNoAlternativeJob) {
   ProxyConfig proxy_config;
   proxy_config.set_auto_detect(true);
   // Use asynchronous proxy resolver.
   MockAsyncProxyResolverFactory* proxy_resolver_factory =
       new MockAsyncProxyResolverFactory(false);
   session_deps_.proxy_service.reset(new ProxyService(
       base::WrapUnique(new ProxyConfigServiceFixed(proxy_config)),
       base::WrapUnique(proxy_resolver_factory), nullptr));
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("http://www.google.com");
 
   request_.reset(
       job_controller_->Start(request_info, &request_delegate_, nullptr,
                              BoundNetLog(), HttpStreamRequest::HTTP_STREAM,
                              DEFAULT_PRIORITY, SSLConfig(), SSLConfig()));
 
@@ skipping 13 matching lines @@
 // before any Job is bound to Request.
 TEST_F(HttpStreamFactoryImplJobControllerTest, CancelJobsBeforeBinding) {
   ProxyConfig proxy_config;
   proxy_config.set_auto_detect(true);
   // Use asynchronous proxy resolver.
   MockAsyncProxyResolverFactory* proxy_resolver_factory =
       new MockAsyncProxyResolverFactory(false);
   session_deps_.proxy_service.reset(new ProxyService(
       base::WrapUnique(new ProxyConfigServiceFixed(proxy_config)),
       base::WrapUnique(proxy_resolver_factory), nullptr));
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("https://www.google.com");
 
   url::SchemeHostPort server(request_info.url);
   AlternativeService alternative_service(QUIC, server.host(), 443);
   SetAlternativeService(request_info, alternative_service);
 
   request_.reset(
@@ skipping 12 matching lines @@
 
 TEST_F(HttpStreamFactoryImplJobControllerTest, OnStreamFailedForBothJobs) {
   ProxyConfig proxy_config;
   proxy_config.set_auto_detect(true);
   // Use asynchronous proxy resolver.
   MockAsyncProxyResolverFactory* proxy_resolver_factory =
       new MockAsyncProxyResolverFactory(false);
   session_deps_.proxy_service.reset(new ProxyService(
       base::WrapUnique(new ProxyConfigServiceFixed(proxy_config)),
       base::WrapUnique(proxy_resolver_factory), nullptr));
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("https://www.google.com");
 
   url::SchemeHostPort server(request_info.url);
   AlternativeService alternative_service(QUIC, server.host(), 443);
   SetAlternativeService(request_info, alternative_service);
 
   request_.reset(
@@ skipping 23 matching lines @@
 TEST_F(HttpStreamFactoryImplJobControllerTest,
        SecondJobFailsAfterFirstJobSucceeds) {
   ProxyConfig proxy_config;
   proxy_config.set_auto_detect(true);
   // Use asynchronous proxy resolver.
   MockAsyncProxyResolverFactory* proxy_resolver_factory =
       new MockAsyncProxyResolverFactory(false);
   session_deps_.proxy_service.reset(new ProxyService(
       base::WrapUnique(new ProxyConfigServiceFixed(proxy_config)),
       base::WrapUnique(proxy_resolver_factory), nullptr));
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("https://www.google.com");
 
   url::SchemeHostPort server(request_info.url);
   AlternativeService alternative_service(QUIC, server.host(), 443);
   SetAlternativeService(request_info, alternative_service);
 
   request_.reset(
@@ skipping 31 matching lines @@
 TEST_F(HttpStreamFactoryImplJobControllerTest,
        SecondJobSucceedsAfterFirstJobFailed) {
   ProxyConfig proxy_config;
   proxy_config.set_auto_detect(true);
   // Use asynchronous proxy resolver.
   MockAsyncProxyResolverFactory* proxy_resolver_factory =
       new MockAsyncProxyResolverFactory(false);
   session_deps_.proxy_service.reset(new ProxyService(
       base::WrapUnique(new ProxyConfigServiceFixed(proxy_config)),
       base::WrapUnique(proxy_resolver_factory), nullptr));
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("https://www.google.com");
 
   url::SchemeHostPort server(request_info.url);
   AlternativeService alternative_service(QUIC, server.host(), 443);
   SetAlternativeService(request_info, alternative_service);
 
   request_.reset(
@@ skipping 27 matching lines @@
 // Get load state after main job fails and before alternative job succeeds.
 TEST_F(HttpStreamFactoryImplJobControllerTest, GetLoadStateAfterMainJobFailed) {
   ProxyConfig proxy_config;
   proxy_config.set_auto_detect(true);
   // Use asynchronous proxy resolver.
   MockAsyncProxyResolverFactory* proxy_resolver_factory =
       new MockAsyncProxyResolverFactory(false);
   session_deps_.proxy_service.reset(new ProxyService(
       base::WrapUnique(new ProxyConfigServiceFixed(proxy_config)),
       base::WrapUnique(proxy_resolver_factory), nullptr));
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("https://www.google.com");
 
   url::SchemeHostPort server(request_info.url);
   AlternativeService alternative_service(QUIC, server.host(), 443);
   SetAlternativeService(request_info, alternative_service);
 
   request_.reset(
@@ skipping 30 matching lines @@
   // Use failing ProxyResolverFactory which is unable to create ProxyResolver
   // to stall the alternative job and report to controller to maybe resume the
   // main job.
   ProxyConfig proxy_config;
   proxy_config.set_auto_detect(true);
   proxy_config.set_pac_mandatory(true);
   session_deps_.proxy_service.reset(new ProxyService(
       base::WrapUnique(new ProxyConfigServiceFixed(proxy_config)),
       base::WrapUnique(new FailingProxyResolverFactory), nullptr));
 
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("https://www.google.com");
 
   url::SchemeHostPort server(request_info.url);
   AlternativeService alternative_service(QUIC, server.host(), 443);
   SetAlternativeService(request_info, alternative_service);
 
   request_.reset(
       job_controller_->Start(request_info, &request_delegate_, nullptr,
                              BoundNetLog(), HttpStreamRequest::HTTP_STREAM,
                              DEFAULT_PRIORITY, SSLConfig(), SSLConfig()));
   EXPECT_TRUE(job_controller_->main_job());
   EXPECT_TRUE(job_controller_->alternative_job());
 
   // Wait until OnStreamFailedCallback is executed on the alternative job.
   EXPECT_CALL(request_delegate_, OnStreamFailed(_, _)).Times(1);
   EXPECT_CALL(*job_factory_.main_job(), MarkOtherJobComplete(_)).Times(1);
   base::RunLoop().RunUntilIdle();
 }
 
 TEST_F(HttpStreamFactoryImplJobControllerTest, InvalidPortForQuic) {
   // Using a restricted port 101 for QUIC should fail and the alternative job
   // should post OnStreamFailedCall on the controller to resume the main job.
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("https://www.google.com");
 
   url::SchemeHostPort server(request_info.url);
   AlternativeService alternative_service(QUIC, server.host(), 101);
   SetAlternativeService(request_info, alternative_service);
 
   request_.reset(
@@ skipping 21 matching lines @@
   MockAsyncProxyResolverFactory* proxy_resolver_factory =
       new MockAsyncProxyResolverFactory(false);
   session_deps_.proxy_service.reset(new ProxyService(
       base::WrapUnique(new ProxyConfigServiceFixed(proxy_config)),
       base::WrapUnique(proxy_resolver_factory), nullptr));
 
   HangingResolver* host_resolver = new HangingResolver();
   session_deps_.host_resolver.reset(host_resolver);
   session_deps_.host_resolver->set_synchronous_mode(false);
 
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("https://www.google.com");
 
   // Set a SPDY alternative service for the server.
   url::SchemeHostPort server(request_info.url);
   AlternativeService alternative_service(QUIC, server.host(), 443);
   SetAlternativeService(request_info, alternative_service);
   // Hack to use different URL for the main job to help differentiate the proxy
@@ skipping 43 matching lines @@
 
   ProxyConfig proxy_config;
   proxy_config.set_auto_detect(true);
   // Use asynchronous proxy resolver.
   MockAsyncProxyResolverFactory* proxy_resolver_factory =
       new MockAsyncProxyResolverFactory(false);
   session_deps_.proxy_service.reset(new ProxyService(
       base::WrapUnique(new ProxyConfigServiceFixed(proxy_config)),
       base::WrapUnique(proxy_resolver_factory), nullptr));
 
-  Initialize();
+  Initialize(false);
 
   HttpRequestInfo request_info;
   request_info.method = "GET";
   request_info.url = GURL("https://www.google.com");
 
   url::SchemeHostPort server(request_info.url);
   AlternativeService alternative_service(QUIC, server.host(), 443);
   SetAlternativeService(request_info, alternative_service);
   // Hack to use different URL for the main job to help differentiate the proxy
   // requests.
@@ skipping 32 matching lines @@
   EXPECT_CALL(*job_factory_.main_job(), Resume()).Times(1);
   EXPECT_CALL(*job_factory_.main_job(), MarkOtherJobComplete(_)).Times(1);
 
   base::RunLoop().RunUntilIdle();
 }
 
 TEST_F(HttpStreamFactoryImplJobControllerTest, DelayedTCP) {
   HangingResolver* resolver = new HangingResolver();
   session_deps_.host_resolver.reset(resolver);
 
-  Initialize();
+  Initialize(false);
 
   // Enable delayed TCP and set time delay for waiting job.
   QuicStreamFactory* quic_stream_factory = session_->quic_stream_factory();
   test::QuicStreamFactoryPeer::SetDelayTcpRace(quic_stream_factory, true);
   quic_stream_factory->set_require_confirmation(false);
   ServerNetworkStats stats1;
   stats1.srtt = base::TimeDelta::FromMicroseconds(10);
   session_->http_server_properties()->SetServerNetworkStats(
       url::SchemeHostPort(GURL("https://www.google.com")), stats1);
 
@@ skipping 16 matching lines @@
   // The alternative job stalls as host resolution hangs when creating the QUIC
   // request and controller should resume the main job after delay.
   // Verify the waiting time for delayed main job.
   EXPECT_CALL(*job_factory_.main_job(), Resume())
       .WillOnce(Invoke(testing::CreateFunctor(
           &JobControllerPeer::VerifyWaitingTimeForMainJob, job_controller_,
           base::TimeDelta::FromMicroseconds(15))));
 
   base::RunLoop().RunUntilIdle();
 }
+
+// Verifies that the alternative proxty server job is not created if the URL

[RyanSturm, 2016/08/22 16:24:41]

s/proxty/proxy

[tbansal1, 2016/08/23 20:56:41]

Done.

+// scheme is HTTPS.

[Zhongyi Shi, 2016/08/23 05:42:33]

nit: shall we change this test or add another test to cover:
we start 2 jobs: main job, alt service job. And alt service job fails really
early due to invalid port. main job resumes, make sure main job won't create
another alt proxy server job?

[tbansal1, 2016/08/23 20:56:41]

I modified WithQUICAlternativeProxyMarkedAsBad in
http_stream_factory_impl_unittest.cc to test this. Please let me know what you
think.

+TEST_F(HttpStreamFactoryImplJobControllerTest, DelayedTCPHttpsURL) {
+  // Using hanging resolver will cause the alternative job to hang indefinitely.
+  HangingResolver* resolver = new HangingResolver();
+  session_deps_.host_resolver.reset(resolver);
+
+  Initialize(true);
+  EXPECT_TRUE(test_proxy_delegate()->alternative_proxy_server().is_quic());
+
+  // Enable delayed TCP and set time delay for waiting job.

[Zhongyi Shi, 2016/08/23 05:42:33]

You probably don't need this delayed TCP setting up as you are only verifying
that no alt job is created if the URL scheme is HTTPS.

[tbansal1, 2016/08/23 20:56:40]

Done.

+  QuicStreamFactory* quic_stream_factory = session_->quic_stream_factory();
+  test::QuicStreamFactoryPeer::SetDelayTcpRace(quic_stream_factory, true);
+  quic_stream_factory->set_require_confirmation(false);
+  ServerNetworkStats stats1;
+  stats1.srtt = base::TimeDelta::FromMicroseconds(10);
+  session_->http_server_properties()->SetServerNetworkStats(
+      url::SchemeHostPort(GURL("https://myproxy.org")), stats1);
+
+  HttpRequestInfo request_info;
+  request_info.method = "GET";
+  request_info.url = GURL("https://mail.example.org/");
+
+  request_.reset(
+      job_controller_->Start(request_info, &request_delegate_, nullptr,
+                             BoundNetLog(), HttpStreamRequest::HTTP_STREAM,
+                             DEFAULT_PRIORITY, SSLConfig(), SSLConfig()));
+  EXPECT_TRUE(job_controller_->main_job());
+  EXPECT_FALSE(job_controller_->main_job()->is_waiting());
+  EXPECT_FALSE(job_controller_->alternative_job());
+
+  EXPECT_CALL(*job_factory_.main_job(), Resume()).Times(0);
+  base::RunLoop().RunUntilIdle();
+}
+

[Zhongyi Shi, 2016/08/23 05:42:33]

Shall we add a test case where HTTP request doesn't have a proxy server set
shouldn't create a alt proxy server job created?

[tbansal1, 2016/08/23 20:56:40]

Good point. Done. Added test HttpURLWithNoProxy above.

+// Verifies that the main job is resumed properly after a delay when the
+// alternative proxy server job hangs.
+TEST_F(HttpStreamFactoryImplJobControllerTest, DelayedTCPAlternativeProxy) {
+  // Using hanging resolver will cause the alternative job to hang indefinitely.
+  HangingResolver* resolver = new HangingResolver();
+  session_deps_.host_resolver.reset(resolver);
+
+  Initialize(true);
+  EXPECT_TRUE(test_proxy_delegate()->alternative_proxy_server().is_quic());
+
+  // Enable delayed TCP and set time delay for waiting job.
+  QuicStreamFactory* quic_stream_factory = session_->quic_stream_factory();
+  test::QuicStreamFactoryPeer::SetDelayTcpRace(quic_stream_factory, true);
+  quic_stream_factory->set_require_confirmation(false);
+  ServerNetworkStats stats1;
+  stats1.srtt = base::TimeDelta::FromMicroseconds(10);
+  session_->http_server_properties()->SetServerNetworkStats(
+      url::SchemeHostPort(GURL("https://myproxy.org")), stats1);
+
+  HttpRequestInfo request_info;
+  request_info.method = "GET";
+  request_info.url = GURL("http://mail.example.org/");
+
+  request_.reset(
+      job_controller_->Start(request_info, &request_delegate_, nullptr,
+                             BoundNetLog(), HttpStreamRequest::HTTP_STREAM,
+                             DEFAULT_PRIORITY, SSLConfig(), SSLConfig()));
+  EXPECT_TRUE(job_controller_->main_job());
+  EXPECT_TRUE(job_controller_->main_job()->is_waiting());
+  EXPECT_TRUE(job_controller_->alternative_job());
+
+  // The alternative proxy server job stalls when connecting to the alternative
+  // proxy server, and controller should resume the main job after delay.
+  // Verify the waiting time for delayed main job.
+  EXPECT_CALL(*job_factory_.main_job(), Resume())
+      .WillOnce(Invoke(testing::CreateFunctor(
+          &JobControllerPeer::VerifyWaitingTimeForMainJob, job_controller_,
+          base::TimeDelta::FromMicroseconds(15))));
+
+  base::RunLoop().RunUntilIdle();
+  // Since the main job did not complete successfully, the alternative proxy
+  // server should not be marked as bad.
+  EXPECT_TRUE(test_proxy_delegate()->alternative_proxy_server().is_valid());
+}
+
+// Verifies that the alternative proxy server job fails immediately, and the
+// main job is not blocked.
+TEST_F(HttpStreamFactoryImplJobControllerTest, FailAlternativeProxy) {
+  // Using failing resolver will cause the alternative job to fail.
+  FailingHostResolver* resolver = new FailingHostResolver();
+  session_deps_.host_resolver.reset(resolver);
+
+  Initialize(true);
+  EXPECT_TRUE(test_proxy_delegate()->alternative_proxy_server().is_quic());
+
+  // Enable delayed TCP and set time delay for waiting job.
+  QuicStreamFactory* quic_stream_factory = session_->quic_stream_factory();
+  test::QuicStreamFactoryPeer::SetDelayTcpRace(quic_stream_factory, true);
+  quic_stream_factory->set_require_confirmation(false);
+  ServerNetworkStats stats1;
+  stats1.srtt = base::TimeDelta::FromMicroseconds(300 * 1000);
+  session_->http_server_properties()->SetServerNetworkStats(
+      url::SchemeHostPort(GURL("https://myproxy.org")), stats1);
+
+  HttpRequestInfo request_info;
+  request_info.method = "GET";
+  request_info.url = GURL("http://mail.example.org/");
+
+  request_.reset(
+      job_controller_->Start(request_info, &request_delegate_, nullptr,
+                             BoundNetLog(), HttpStreamRequest::HTTP_STREAM,
+                             DEFAULT_PRIORITY, SSLConfig(), SSLConfig()));
+  EXPECT_TRUE(job_controller_->main_job());

[Zhongyi Shi, 2016/08/23 05:42:33]

nit: EXPECT_TRUE(job_controller_->main_job()->is_waiting());

[tbansal1, 2016/08/23 20:56:41]

Done.

+  EXPECT_TRUE(job_controller_->alternative_job());
+
+  EXPECT_CALL(request_delegate_, OnStreamReady(_, _, _)).Times(0);
+  EXPECT_CALL(*job_factory_.main_job(), MarkOtherJobComplete(_)).Times(1);
+
+  // Since the alternative proxy server job is started in the next message loop,
+  // the main job would remain blocked until the alternative proxy starts, and
+  // fails.
+  EXPECT_CALL(*job_factory_.main_job(), Resume())
+      .WillOnce(Invoke(testing::CreateFunctor(
+          &JobControllerPeer::VerifyWaitingTimeForMainJob, job_controller_,
+          base::TimeDelta::FromMicroseconds(0))));
+
+  base::RunLoop().RunUntilIdle();
+  EXPECT_FALSE(job_controller_->alternative_job());
+  EXPECT_TRUE(job_controller_->main_job()->is_waiting());
+  // Since the main job did not complete successfully, the alternative proxy
+  // server should not be marked as bad.
+  EXPECT_TRUE(test_proxy_delegate()->alternative_proxy_server().is_valid());
+}
+
 }  // namespace net