Adds a NetworkChangeNotifier dependency to ProxyService; when we observer a network change through the notifier, the ProxyService re-configures itself.

So for example, if you were to switch to VPN and are using a custom PAC URL, we will re-download that URL on the new network.
Similarly if you are using auto-detect PAC settings, we will re-run the autodiscovery steps for the next resolve.

Note that Chromium is still passing a NULL NetworkChangeNotifier dependency into its ProxyService -- until it passes a real implementation, this will not impact Chrome.

BUG=12293
TEST=ProxyServiceTest.NetworkChangeTriggersPacRefetch
Review URL: http://codereview.chromium.org/525104

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@35772 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 190 insertions, 50 deletions

diff --git a/net/proxy/proxy_service.cc b/net/proxy/proxy_service.cc
index 01a42ac..8160e64 100644
--- a/net/proxy/proxy_service.cc
+++ b/net/proxy/proxy_service.cc
@@ -198,13 +198,18 @@ class ProxyService::PacRequest
 // ProxyService ---------------------------------------------------------------
 
 ProxyService::ProxyService(ProxyConfigService* config_service,
-                           ProxyResolver* resolver)
+                           ProxyResolver* resolver,
+                           NetworkChangeNotifier* network_change_notifier)
     : config_service_(config_service),
       resolver_(resolver),
       next_config_id_(1),
       should_use_proxy_resolver_(false),
       ALLOW_THIS_IN_INITIALIZER_LIST(init_proxy_resolver_callback_(
-          this, &ProxyService::OnInitProxyResolverComplete)) {
+          this, &ProxyService::OnInitProxyResolverComplete)),
+      network_change_notifier_(network_change_notifier) {
+  // Register to receive network change notifications.
+  if (network_change_notifier_)
+    network_change_notifier_->AddObserver(this);
 }
 
 // static
@@ -212,6 +217,7 @@ ProxyService* ProxyService::Create(
     ProxyConfigService* proxy_config_service,
     bool use_v8_resolver,
     URLRequestContext* url_request_context,
+    NetworkChangeNotifier* network_change_notifier,
     MessageLoop* io_loop) {
   ProxyResolver* proxy_resolver;
 
@@ -231,7 +237,7 @@ ProxyService* ProxyService::Create(
   proxy_resolver = new SingleThreadedProxyResolver(proxy_resolver);
 
   ProxyService* proxy_service = new ProxyService(
-      proxy_config_service, proxy_resolver);
+      proxy_config_service, proxy_resolver, network_change_notifier);
 
   if (proxy_resolver->expects_pac_bytes()) {
     // Configure PAC script downloads to be issued using |url_request_context|.
@@ -245,13 +251,15 @@ ProxyService* ProxyService::Create(
 
 // static
 ProxyService* ProxyService::CreateFixed(const ProxyConfig& pc) {
-  return Create(new ProxyConfigServiceFixed(pc), false, NULL, NULL);
+  return Create(new ProxyConfigServiceFixed(pc), false, NULL, NULL, NULL);
 }
 
 // static
 ProxyService* ProxyService::CreateNull() {
   // Use a configuration fetcher and proxy resolver which always fail.
-  return new ProxyService(new ProxyConfigServiceNull, new ProxyResolverNull);
+  return new ProxyService(new ProxyConfigServiceNull,
+                          new ProxyResolverNull,
+                          NULL);
 }
 
 int ProxyService::ResolveProxy(const GURL& raw_url,
@@ -354,6 +362,10 @@ void ProxyService::ApplyProxyRules(const GURL& url,
 }
 
 ProxyService::~ProxyService() {
+  // Unregister to receive network change notifications.
+  if (network_change_notifier_)
+    network_change_notifier_->RemoveObserver(this);
+
   // Cancel any inprogress requests.
   for (PendingRequests::iterator it = pending_requests_.begin();
        it != pending_requests_.end();
@@ -736,6 +748,17 @@ bool ProxyService::IsLocalName(const GURL& url) {
   return host.find('.') == std::string::npos;
 }
 
+void ProxyService::OnIPAddressChanged() {
+  DCHECK(network_change_notifier_);
+
+  // Mark the current configuration as being un-initialized.
+  //
+  // This will force us to re-fetch the configuration (and re-run all of
+  // the initialization steps) on the next ResolveProxy() request, as part
+  // of UpdateConfigIfOld().
+  config_.set_id(ProxyConfig::INVALID_ID);
+}
+
 SyncProxyServiceHelper::SyncProxyServiceHelper(MessageLoop* io_message_loop,
                                                ProxyService* proxy_service)
     : io_message_loop_(io_message_loop),
diff --git a/net/proxy/proxy_service.h b/net/proxy/proxy_service.h
index 857ab93..8cca773 100644
--- a/net/proxy/proxy_service.h
+++ b/net/proxy/proxy_service.h
@@ -12,6 +12,7 @@
 #include "base/scoped_ptr.h"
 #include "base/waitable_event.h"
 #include "net/base/completion_callback.h"
+#include "net/base/network_change_notifier.h"
 #include "net/proxy/proxy_server.h"
 #include "net/proxy/proxy_info.h"
 #include "testing/gtest/include/gtest/gtest_prod.h"
@@ -31,10 +32,15 @@ class ProxyScriptFetcher;
 // This class can be used to resolve the proxy server to use when loading a
 // HTTP(S) URL.  It uses the given ProxyResolver to handle the actual proxy
 // resolution.  See ProxyResolverV8 for example.
-class ProxyService : public base::RefCountedThreadSafe<ProxyService> {
+class ProxyService : public base::RefCountedThreadSafe<ProxyService>,
+                     public NetworkChangeNotifier::Observer {
  public:
   // The instance takes ownership of |config_service| and |resolver|.
-  ProxyService(ProxyConfigService* config_service, ProxyResolver* resolver);
+  // If |network_change_notifier| is non-NULL, the proxy service will register
+  // with it to detect when the network setup has changed. This is used to
+  // decide when to re-configure the proxy discovery.
+  ProxyService(ProxyConfigService* config_service, ProxyResolver* resolver,
+               NetworkChangeNotifier* network_change_notifier);
 
   // Used internally to handle PAC queries.
   // TODO(eroman): consider naming this simply "Request".
@@ -126,6 +132,8 @@ class ProxyService : public base::RefCountedThreadSafe<ProxyService> {
   // |url_request_context| is only used when use_v8_resolver is true:
   // it specifies the URL request context that will be used if a PAC
   // script needs to be fetched.
+  // |network_change_notifier| may be NULL. Otherwise it will be used to
+  // signal the ProxyService when the network setup has changed.
   // |io_loop| points to the IO thread's message loop. It is only used
   // when pc is NULL.
   // ##########################################################################
@@ -137,6 +145,7 @@ class ProxyService : public base::RefCountedThreadSafe<ProxyService> {
       ProxyConfigService* proxy_config_service,
       bool use_v8_resolver,
       URLRequestContext* url_request_context,
+      NetworkChangeNotifier* network_change_notifier,
       MessageLoop* io_loop);
 
   // Convenience method that creates a proxy service using the
@@ -238,6 +247,9 @@ class ProxyService : public base::RefCountedThreadSafe<ProxyService> {
   // heuristic).
   static bool IsLocalName(const GURL& url);
 
+  // NetworkChangeNotifier::Observer methods:
+  virtual void OnIPAddressChanged();
+
   scoped_ptr<ProxyConfigService> config_service_;
   scoped_ptr<ProxyResolver> resolver_;
 
@@ -277,6 +289,10 @@ class ProxyService : public base::RefCountedThreadSafe<ProxyService> {
   // Log from the *last* time |init_proxy_resolver_.Init()| was called, or NULL.
   scoped_refptr<LoadLog> init_proxy_resolver_log_;
 
+  // The (possibly NULL) network change notifier that we use to decide when
+  // to refetch PAC scripts or re-run WPAD.
+  scoped_refptr<NetworkChangeNotifier> network_change_notifier_;
+
   DISALLOW_COPY_AND_ASSIGN(ProxyService);
 };
 
diff --git a/net/proxy/proxy_service_unittest.cc b/net/proxy/proxy_service_unittest.cc
index c256a44..f220ce1 100644
--- a/net/proxy/proxy_service_unittest.cc
+++ b/net/proxy/proxy_service_unittest.cc
@@ -12,6 +12,7 @@
 #include "googleurl/src/gurl.h"
 #include "net/base/load_log.h"
 #include "net/base/load_log_unittest.h"
+#include "net/base/mock_network_change_notifier.h"
 #include "net/base/net_errors.h"
 #include "net/base/test_completion_callback.h"
 #include "net/proxy/mock_proxy_resolver.h"
@@ -91,7 +92,7 @@ class MockProxyScriptFetcher : public ProxyScriptFetcher {
 TEST(ProxyServiceTest, Direct) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
   scoped_refptr<ProxyService> service(
-      new ProxyService(new MockProxyConfigService, resolver));
+      new ProxyService(new MockProxyConfigService, resolver, NULL));
 
   GURL url("http://www.google.com/");
 
@@ -118,7 +119,7 @@ TEST(ProxyServiceTest, PAC) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   GURL url("http://www.google.com/");
 
@@ -163,7 +164,7 @@ TEST(ProxyServiceTest, PAC_NoIdentityOrHash) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   GURL url("http://username:password@www.google.com/?ref#hash#hash");
 
@@ -191,7 +192,7 @@ TEST(ProxyServiceTest, PAC_FailoverWithoutDirect) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   GURL url("http://www.google.com/");
 
@@ -248,7 +249,7 @@ TEST(ProxyServiceTest, PAC_FailoverAfterDirect) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   GURL url("http://www.google.com/");
 
@@ -310,7 +311,7 @@ TEST(ProxyServiceTest, ProxyResolverFails) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   // Start first resolve request.
   GURL url("http://www.google.com/");
@@ -360,7 +361,7 @@ TEST(ProxyServiceTest, ProxyFallback) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   GURL url("http://www.google.com/");
 
@@ -438,7 +439,7 @@ TEST(ProxyServiceTest, ProxyFallbackToDirect) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   GURL url("http://www.google.com/");
 
@@ -498,7 +499,7 @@ TEST(ProxyServiceTest, ProxyFallback_NewSettings) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   GURL url("http://www.google.com/");
 
@@ -587,7 +588,7 @@ TEST(ProxyServiceTest, ProxyFallback_BadConfig) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   GURL url("http://www.google.com/");
 
@@ -671,7 +672,9 @@ TEST(ProxyServiceTest, ProxyBypassList) {
 
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver()));
+        new MockProxyConfigService(config),
+        new MockAsyncProxyResolver(),
+        NULL));
     GURL url("http://www.google.com/");
     // Get the proxy information.
     TestCompletionCallback callback;
@@ -682,7 +685,9 @@ TEST(ProxyServiceTest, ProxyBypassList) {
 
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver()));
+        new MockProxyConfigService(config),
+        new MockAsyncProxyResolver(),
+        NULL));
     GURL test_url("http://local");
     TestCompletionCallback callback;
     int rv = service->ResolveProxy(test_url, &info, &callback, NULL, NULL);
@@ -695,7 +700,7 @@ TEST(ProxyServiceTest, ProxyBypassList) {
   config.proxy_bypass_local_names = true;
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("http://www.webkit.org");
     TestCompletionCallback callback;
     int rv = service->ResolveProxy(test_url, &info, &callback, NULL, NULL);
@@ -709,7 +714,7 @@ TEST(ProxyServiceTest, ProxyBypassList) {
   config.proxy_bypass_local_names = true;
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("http://74.125.19.147");
     TestCompletionCallback callback;
     int rv = service->ResolveProxy(test_url, &info, &callback, NULL, NULL);
@@ -722,7 +727,7 @@ TEST(ProxyServiceTest, ProxyBypassList) {
   config.proxy_bypass_local_names = true;
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("http://www.msn.com");
     TestCompletionCallback callback;
     int rv = service->ResolveProxy(test_url, &info, &callback, NULL, NULL);
@@ -735,7 +740,7 @@ TEST(ProxyServiceTest, ProxyBypassList) {
   config.proxy_bypass_local_names = true;
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("http://www.msnbc.msn.com");
     TestCompletionCallback callback;
     int rv = service->ResolveProxy(test_url, &info, &callback, NULL, NULL);
@@ -748,7 +753,7 @@ TEST(ProxyServiceTest, ProxyBypassList) {
   config.proxy_bypass_local_names = true;
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("HTTP://WWW.MSNBC.MSN.COM");
     TestCompletionCallback callback;
     int rv = service->ResolveProxy(test_url, &info, &callback, NULL, NULL);
@@ -769,7 +774,7 @@ TEST(ProxyServiceTest, ProxyBypassListWithPorts) {
   config.proxy_bypass.push_back("*.example.com:99");
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     {
       GURL test_url("http://www.example.com:99");
       TestCompletionCallback callback;
@@ -797,7 +802,7 @@ TEST(ProxyServiceTest, ProxyBypassListWithPorts) {
   config.proxy_bypass.push_back("*.example.com:80");
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("http://www.example.com");
     TestCompletionCallback callback;
     int rv = service->ResolveProxy(test_url, &info, &callback, NULL, NULL);
@@ -809,7 +814,7 @@ TEST(ProxyServiceTest, ProxyBypassListWithPorts) {
   config.proxy_bypass.push_back("*.example.com");
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("http://www.example.com:99");
     TestCompletionCallback callback;
     int rv = service->ResolveProxy(test_url, &info, &callback, NULL, NULL);
@@ -822,7 +827,7 @@ TEST(ProxyServiceTest, ProxyBypassListWithPorts) {
   config.proxy_bypass.push_back("[3ffe:2a00:100:7031::1]:99");
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     {
       GURL test_url("http://[3ffe:2a00:100:7031::1]:99/");
       TestCompletionCallback callback;
@@ -846,7 +851,7 @@ TEST(ProxyServiceTest, ProxyBypassListWithPorts) {
   config.proxy_bypass.push_back("[3ffe:2a00:100:7031::1]");
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     {
       GURL test_url("http://[3ffe:2a00:100:7031::1]:99/");
       TestCompletionCallback callback;
@@ -870,7 +875,7 @@ TEST(ProxyServiceTest, PerProtocolProxyTests) {
   config.auto_detect = false;
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("http://www.msn.com");
     ProxyInfo info;
     TestCompletionCallback callback;
@@ -881,7 +886,7 @@ TEST(ProxyServiceTest, PerProtocolProxyTests) {
   }
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("ftp://ftp.google.com");
     ProxyInfo info;
     TestCompletionCallback callback;
@@ -892,7 +897,7 @@ TEST(ProxyServiceTest, PerProtocolProxyTests) {
   }
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("https://webbranch.techcu.com");
     ProxyInfo info;
     TestCompletionCallback callback;
@@ -904,7 +909,7 @@ TEST(ProxyServiceTest, PerProtocolProxyTests) {
   {
     config.proxy_rules.ParseFromString("foopy1:8080");
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("http://www.microsoft.com");
     ProxyInfo info;
     TestCompletionCallback callback;
@@ -926,7 +931,7 @@ TEST(ProxyServiceTest, DefaultProxyFallbackToSOCKS) {
 
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("http://www.msn.com");
     ProxyInfo info;
     TestCompletionCallback callback;
@@ -937,7 +942,7 @@ TEST(ProxyServiceTest, DefaultProxyFallbackToSOCKS) {
   }
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("ftp://ftp.google.com");
     ProxyInfo info;
     TestCompletionCallback callback;
@@ -948,7 +953,7 @@ TEST(ProxyServiceTest, DefaultProxyFallbackToSOCKS) {
   }
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("https://webbranch.techcu.com");
     ProxyInfo info;
     TestCompletionCallback callback;
@@ -959,7 +964,7 @@ TEST(ProxyServiceTest, DefaultProxyFallbackToSOCKS) {
   }
   {
     scoped_refptr<ProxyService> service(new ProxyService(
-        new MockProxyConfigService(config), new MockAsyncProxyResolver));
+        new MockProxyConfigService(config), new MockAsyncProxyResolver, NULL));
     GURL test_url("unknown://www.microsoft.com");
     ProxyInfo info;
     TestCompletionCallback callback;
@@ -978,7 +983,7 @@ TEST(ProxyServiceTest, CancelInProgressRequest) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   // Start 3 requests.
 
@@ -1053,7 +1058,7 @@ TEST(ProxyServiceTest, InitialPACScriptDownload) {
       new MockAsyncProxyResolverExpectsBytes;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service->SetProxyScriptFetcher(fetcher);
@@ -1132,7 +1137,7 @@ TEST(ProxyServiceTest, ChangeScriptFetcherWhilePACDownloadInProgress) {
       new MockAsyncProxyResolverExpectsBytes;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service->SetProxyScriptFetcher(fetcher);
@@ -1189,7 +1194,7 @@ TEST(ProxyServiceTest, CancelWhilePACFetching) {
       new MockAsyncProxyResolverExpectsBytes;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service->SetProxyScriptFetcher(fetcher);
@@ -1274,7 +1279,7 @@ TEST(ProxyServiceTest, FallbackFromAutodetectToCustomPac) {
   MockAsyncProxyResolverExpectsBytes* resolver =
       new MockAsyncProxyResolverExpectsBytes;
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service->SetProxyScriptFetcher(fetcher);
@@ -1345,7 +1350,7 @@ TEST(ProxyServiceTest, FallbackFromAutodetectToCustomPac2) {
   MockAsyncProxyResolverExpectsBytes* resolver =
       new MockAsyncProxyResolverExpectsBytes;
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service->SetProxyScriptFetcher(fetcher);
@@ -1421,7 +1426,7 @@ TEST(ProxyServiceTest, FallbackFromAutodetectToCustomToManual) {
   MockAsyncProxyResolverExpectsBytes* resolver =
       new MockAsyncProxyResolverExpectsBytes;
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service->SetProxyScriptFetcher(fetcher);
@@ -1479,7 +1484,7 @@ TEST(ProxyServiceTest, BypassDoesntApplyToPac) {
   MockAsyncProxyResolverExpectsBytes* resolver =
       new MockAsyncProxyResolverExpectsBytes;
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service->SetProxyScriptFetcher(fetcher);
@@ -1547,7 +1552,7 @@ TEST(ProxyServiceTest, DeleteWhileInitProxyResolverHasOutstandingFetch) {
   MockAsyncProxyResolverExpectsBytes* resolver =
       new MockAsyncProxyResolverExpectsBytes;
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
   service->SetProxyScriptFetcher(fetcher);
@@ -1583,7 +1588,7 @@ TEST(ProxyServiceTest, DeleteWhileInitProxyResolverHasOutstandingSet) {
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
 
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   GURL url("http://www.google.com/");
 
@@ -1604,7 +1609,9 @@ TEST(ProxyServiceTest, ResetProxyConfigService) {
   config1.proxy_rules.ParseFromString("foopy1:8080");
   config1.auto_detect = false;
   scoped_refptr<ProxyService> service(new ProxyService(
-      new MockProxyConfigService(config1), new MockAsyncProxyResolverExpectsBytes));
+      new MockProxyConfigService(config1),
+      new MockAsyncProxyResolverExpectsBytes,
+      NULL));
 
   ProxyInfo info;
   TestCompletionCallback callback1;
@@ -1677,7 +1684,7 @@ TEST(ProxyServiceTest, UpdateConfigAfterFailedAutodetect) {
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   // Start 1 requests.
 
@@ -1723,7 +1730,7 @@ TEST(ProxyServiceTest, UpdateConfigFromPACToDirect) {
   MockProxyConfigService* config_service = new MockProxyConfigService(config);
   MockAsyncProxyResolver* resolver = new MockAsyncProxyResolver;
   scoped_refptr<ProxyService> service(
-      new ProxyService(config_service, resolver));
+      new ProxyService(config_service, resolver, NULL));
 
   // Start 1 request.
 
@@ -1768,4 +1775,98 @@ TEST(ProxyServiceTest, UpdateConfigFromPACToDirect) {
   EXPECT_TRUE(info2.is_direct());
 }
 
+TEST(ProxyServiceTest, NetworkChangeTriggersPacRefetch) {
+  MockProxyConfigService* config_service =
+      new MockProxyConfigService("http://foopy/proxy.pac");
+
+  MockAsyncProxyResolverExpectsBytes* resolver =
+      new MockAsyncProxyResolverExpectsBytes;
+
+  scoped_refptr<MockNetworkChangeNotifier> network_change_notifier(
+      new MockNetworkChangeNotifier());
+
+  scoped_refptr<ProxyService> service(
+      new ProxyService(config_service, resolver, network_change_notifier));
+
+  MockProxyScriptFetcher* fetcher = new MockProxyScriptFetcher;
+  service->SetProxyScriptFetcher(fetcher);
+
+  // Start 1 request.
+
+  ProxyInfo info1;
+  TestCompletionCallback callback1;
+  int rv = service->ResolveProxy(
+      GURL("http://request1"), &info1, &callback1, NULL, NULL);
+  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 resolver yet.
+  EXPECT_TRUE(resolver->pending_requests().empty());
+
+  // At this point the ProxyService should be waiting for the
+  // ProxyScriptFetcher to invoke its completion callback, notifying it of
+  // PAC script download completion.
+  fetcher->NotifyFetchCompletion(OK, "pac-v1");
+
+  // Now that the PAC script is downloaded, the request will have been sent to
+  // the proxy resolver.
+  EXPECT_EQ("pac-v1", resolver->pending_set_pac_script_request()->pac_bytes());
+  resolver->pending_set_pac_script_request()->CompleteNow(OK);
+
+  ASSERT_EQ(1u, resolver->pending_requests().size());
+  EXPECT_EQ(GURL("http://request1"), resolver->pending_requests()[0]->url());
+
+  // Complete the pending request.
+  resolver->pending_requests()[0]->results()->UseNamedProxy("request1:80");
+  resolver->pending_requests()[0]->CompleteNow(OK);
+
+  // Wait for completion callback, and verify that the request ran as expected.
+  EXPECT_EQ(OK, callback1.WaitForResult());
+  EXPECT_EQ("request1:80", info1.proxy_server().ToURI());
+
+  // 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.
+
+  network_change_notifier->NotifyIPAddressChange();
+
+  // Start a second request.
+  ProxyInfo info2;
+  TestCompletionCallback callback2;
+  rv = service->ResolveProxy(
+      GURL("http://request2"), &info2, &callback2, NULL, NULL);
+  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 resolver yet.
+  EXPECT_TRUE(resolver->pending_requests().empty());
+
+  // Simulate the PAC script fetch as having completed (this time with
+  // different data).
+  fetcher->NotifyFetchCompletion(OK, "pac-v2");
+
+  // Now that the PAC script is downloaded, the second request will have been
+  // sent to the proxy resolver.
+  EXPECT_EQ("pac-v2", resolver->pending_set_pac_script_request()->pac_bytes());
+  resolver->pending_set_pac_script_request()->CompleteNow(OK);
+
+  ASSERT_EQ(1u, resolver->pending_requests().size());
+  EXPECT_EQ(GURL("http://request2"), resolver->pending_requests()[0]->url());
+
+  // Complete the pending second request.
+  resolver->pending_requests()[0]->results()->UseNamedProxy("request2:80");
+  resolver->pending_requests()[0]->CompleteNow(OK);
+
+  // Wait for completion callback, and verify that the request ran as expected.
+  EXPECT_EQ(OK, callback2.WaitForResult());
+  EXPECT_EQ("request2:80", info2.proxy_server().ToURI());
+}
+
 }  // namespace net