Lifecycle management for PolicyProviders

The ConfigurationPolicyProviderKeeper (and therefore the individual ConfigurationPolicyProviders) is now a member variable of the BrowserProcess instead of a singleton. This fixes memory leaks at the cost of slightly more complicated shutdown (the PolicyProviders must die while the file thread is still alive, but the preference system observing the providers for policy changes lives longer than that).

BUG=66054, 66102
TEST=existing unit tests; valgrind

Review URL: http://codereview.chromium.org/5962016

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@70496 0039d316-1c4b-4281-b951-d872f2087c98

16 files changed, 249 insertions, 188 deletions

diff --git a/chrome/browser/policy/asynchronous_policy_loader.cc b/chrome/browser/policy/asynchronous_policy_loader.cc
index 6ccae7a..f06ead7 100644
--- a/chrome/browser/policy/asynchronous_policy_loader.cc
+++ b/chrome/browser/policy/asynchronous_policy_loader.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -38,6 +38,9 @@ void AsynchronousPolicyLoader::Stop() {
   if (!stopped_) {
     stopped_ = true;
     delegate_.reset();
+    FOR_EACH_OBSERVER(ConfigurationPolicyProvider::Observer,
+                      observer_list_,
+                      OnProviderGoingAway());
     BrowserThread::PostTask(
         BrowserThread::FILE, FROM_HERE,
         NewRunnableMethod(this, &AsynchronousPolicyLoader::StopOnFileThread));
diff --git a/chrome/browser/policy/asynchronous_policy_loader_unittest.cc b/chrome/browser/policy/asynchronous_policy_loader_unittest.cc
index 3cc416c..44ab3c2 100644
--- a/chrome/browser/policy/asynchronous_policy_loader_unittest.cc
+++ b/chrome/browser/policy/asynchronous_policy_loader_unittest.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -18,6 +18,7 @@ class MockConfigurationPolicyObserver
     : public ConfigurationPolicyProvider::Observer {
  public:
   MOCK_METHOD0(OnUpdatePolicy, void());
+  void OnProviderGoingAway() {}
 };
 
 class AsynchronousPolicyLoaderTest : public AsynchronousPolicyTestBase {
@@ -120,8 +121,7 @@ TEST_F(AsynchronousPolicyLoaderTest, ProviderNotificationOnPolicyChange) {
   AsynchronousPolicyProvider provider(NULL, loader);
   // |registrar| must be declared last so that it is destroyed first.
   ConfigurationPolicyObserverRegistrar registrar;
-  registrar.Init(&provider);
-  registrar.AddObserver(&observer);
+  registrar.Init(&provider, &observer);
   loop_.RunAllPending();
   loader->Reload();
   loop_.RunAllPending();
diff --git a/chrome/browser/policy/configuration_policy_pref_store.cc b/chrome/browser/policy/configuration_policy_pref_store.cc
index 1dc917a..a942bfc 100644
--- a/chrome/browser/policy/configuration_policy_pref_store.cc
+++ b/chrome/browser/policy/configuration_policy_pref_store.cc
@@ -1,9 +1,10 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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 "chrome/browser/policy/configuration_policy_pref_store.h"
 
+#include <map>
 #include <set>
 #include <string>
 #include <vector>
@@ -11,29 +12,21 @@
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
-#include "base/path_service.h"
 #include "base/stl_util-inl.h"
 #include "base/string16.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "base/values.h"
+#include "chrome/browser/browser_process.h"
 #include "chrome/browser/policy/configuration_policy_provider.h"
-#if defined(OS_WIN)
-#include "chrome/browser/policy/configuration_policy_provider_win.h"
-#elif defined(OS_MACOSX)
-#include "chrome/browser/policy/configuration_policy_provider_mac.h"
-#elif defined(OS_POSIX)
-#include "chrome/browser/policy/config_dir_policy_provider.h"
-#endif
+#include "chrome/browser/policy/configuration_policy_provider_keeper.h"
 #include "chrome/browser/policy/device_management_policy_provider.h"
-#include "chrome/browser/policy/dummy_configuration_policy_provider.h"
 #include "chrome/browser/policy/profile_policy_context.h"
 #include "chrome/browser/prefs/pref_value_map.h"
 #include "chrome/browser/prefs/proxy_prefs.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search_engines/search_terms_data.h"
 #include "chrome/browser/search_engines/template_url.h"
-#include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/notification_service.h"
 #include "chrome/common/policy_constants.h"
@@ -620,94 +613,6 @@ bool ConfigurationPolicyPrefKeeper::HasProxyPolicy(
          iter->second && !iter->second->IsType(Value::TYPE_NULL);
 }
 
-namespace {
-
-// Manages the lifecycle of the shared platform-specific policy providers for
-// managed platform, device management and recommended policy. Instantiated as a
-// Singleton.
-class ConfigurationPolicyProviderKeeper {
- public:
-  ConfigurationPolicyProviderKeeper()
-      : managed_platform_provider_(CreateManagedPlatformProvider()),
-        device_management_provider_(CreateDeviceManagementProvider()),
-        recommended_provider_(CreateRecommendedProvider()) {}
-  virtual ~ConfigurationPolicyProviderKeeper() {}
-
-  ConfigurationPolicyProvider* managed_platform_provider() const {
-    return managed_platform_provider_.get();
-  }
-
-  ConfigurationPolicyProvider* device_management_provider() const {
-    return device_management_provider_.get();
-  }
-
-  ConfigurationPolicyProvider* recommended_provider() const {
-    return recommended_provider_.get();
-  }
-
- private:
-  scoped_ptr<ConfigurationPolicyProvider> managed_platform_provider_;
-  scoped_ptr<ConfigurationPolicyProvider> device_management_provider_;
-  scoped_ptr<ConfigurationPolicyProvider> recommended_provider_;
-
-  static ConfigurationPolicyProvider* CreateManagedPlatformProvider();
-  static ConfigurationPolicyProvider* CreateDeviceManagementProvider();
-  static ConfigurationPolicyProvider* CreateRecommendedProvider();
-
-  DISALLOW_COPY_AND_ASSIGN(ConfigurationPolicyProviderKeeper);
-};
-
-static base::LazyInstance<ConfigurationPolicyProviderKeeper>
-    g_configuration_policy_provider_keeper(base::LINKER_INITIALIZED);
-
-ConfigurationPolicyProvider*
-ConfigurationPolicyProviderKeeper::CreateManagedPlatformProvider() {
-  const ConfigurationPolicyProvider::PolicyDefinitionList* policy_list =
-      ConfigurationPolicyPrefStore::GetChromePolicyDefinitionList();
-#if defined(OS_WIN)
-  return new ConfigurationPolicyProviderWin(policy_list);
-#elif defined(OS_MACOSX)
-  return new ConfigurationPolicyProviderMac(policy_list);
-#elif defined(OS_POSIX)
-  FilePath config_dir_path;
-  if (PathService::Get(chrome::DIR_POLICY_FILES, &config_dir_path)) {
-    return new ConfigDirPolicyProvider(
-        policy_list,
-        config_dir_path.Append(FILE_PATH_LITERAL("managed")));
-  } else {
-    return new DummyConfigurationPolicyProvider(policy_list);
-  }
-#else
-  return new DummyConfigurationPolicyProvider(policy_list);
-#endif
-}
-
-ConfigurationPolicyProvider*
-ConfigurationPolicyProviderKeeper::CreateDeviceManagementProvider() {
-  return new DummyConfigurationPolicyProvider(
-      ConfigurationPolicyPrefStore::GetChromePolicyDefinitionList());
-}
-
-ConfigurationPolicyProvider*
-ConfigurationPolicyProviderKeeper::CreateRecommendedProvider() {
-  const ConfigurationPolicyProvider::PolicyDefinitionList* policy_list =
-      ConfigurationPolicyPrefStore::GetChromePolicyDefinitionList();
-#if defined(OS_POSIX) && !defined(OS_MACOSX)
-  FilePath config_dir_path;
-  if (PathService::Get(chrome::DIR_POLICY_FILES, &config_dir_path)) {
-    return new ConfigDirPolicyProvider(
-        policy_list,
-        config_dir_path.Append(FILE_PATH_LITERAL("recommended")));
-  } else {
-    return new DummyConfigurationPolicyProvider(policy_list);
-  }
-#else
-  return new DummyConfigurationPolicyProvider(policy_list);
-#endif
-}
-
-}  // namespace
-
 ConfigurationPolicyPrefStore::ConfigurationPolicyPrefStore(
     ConfigurationPolicyProvider* provider)
     : provider_(provider),
@@ -715,8 +620,7 @@ ConfigurationPolicyPrefStore::ConfigurationPolicyPrefStore(
   // Read initial policy.
   policy_keeper_.reset(new ConfigurationPolicyPrefKeeper(provider));
 
-  registrar_.Init(provider_);
-  registrar_.AddObserver(this);
+  registrar_.Init(provider_, this);
 }
 
 ConfigurationPolicyPrefStore::~ConfigurationPolicyPrefStore() {
@@ -745,11 +649,16 @@ void ConfigurationPolicyPrefStore::OnUpdatePolicy() {
   Refresh();
 }
 
+void ConfigurationPolicyPrefStore::OnProviderGoingAway() {
+  provider_ = NULL;
+}
+
 // static
 ConfigurationPolicyPrefStore*
 ConfigurationPolicyPrefStore::CreateManagedPlatformPolicyPrefStore() {
-  return new ConfigurationPolicyPrefStore(
-      g_configuration_policy_provider_keeper.Get().managed_platform_provider());
+  ConfigurationPolicyProviderKeeper* keeper =
+      g_browser_process->configuration_policy_provider_keeper();
+  return new ConfigurationPolicyPrefStore(keeper->managed_platform_provider());
 }
 
 // static
@@ -757,7 +666,7 @@ ConfigurationPolicyPrefStore*
 ConfigurationPolicyPrefStore::CreateDeviceManagementPolicyPrefStore(
     Profile* profile) {
   ConfigurationPolicyProviderKeeper* keeper =
-      g_configuration_policy_provider_keeper.Pointer();
+      g_browser_process->configuration_policy_provider_keeper();
   ConfigurationPolicyProvider* provider = NULL;
   if (profile)
     provider = profile->GetPolicyContext()->GetDeviceManagementPolicyProvider();
@@ -769,8 +678,9 @@ ConfigurationPolicyPrefStore::CreateDeviceManagementPolicyPrefStore(
 // static
 ConfigurationPolicyPrefStore*
 ConfigurationPolicyPrefStore::CreateRecommendedPolicyPrefStore() {
-  return new ConfigurationPolicyPrefStore(
-      g_configuration_policy_provider_keeper.Get().recommended_provider());
+  ConfigurationPolicyProviderKeeper* keeper =
+      g_browser_process->configuration_policy_provider_keeper();
+  return new ConfigurationPolicyPrefStore(keeper->recommended_provider());
 }
 
 /* static */
@@ -878,6 +788,9 @@ ConfigurationPolicyPrefStore::GetChromePolicyDefinitionList() {
 }
 
 void ConfigurationPolicyPrefStore::Refresh() {
+  if (!provider_)
+    return;
+
   // Construct a new keeper, determine what changed and swap the keeper in.
   scoped_ptr<ConfigurationPolicyPrefKeeper> new_keeper(
       new ConfigurationPolicyPrefKeeper(provider_));
diff --git a/chrome/browser/policy/configuration_policy_pref_store.h b/chrome/browser/policy/configuration_policy_pref_store.h
index 526d884..93b2a4a 100644
--- a/chrome/browser/policy/configuration_policy_pref_store.h
+++ b/chrome/browser/policy/configuration_policy_pref_store.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -42,6 +42,7 @@ class ConfigurationPolicyPrefStore
 
   // ConfigurationPolicyProvider::Observer methods:
   virtual void OnUpdatePolicy();
+  virtual void OnProviderGoingAway();
 
   // Creates a ConfigurationPolicyPrefStore that reads managed platform policy.
   static ConfigurationPolicyPrefStore* CreateManagedPlatformPolicyPrefStore();
diff --git a/chrome/browser/policy/configuration_policy_provider.cc b/chrome/browser/policy/configuration_policy_provider.cc
index 2aee046..3b82134 100644
--- a/chrome/browser/policy/configuration_policy_provider.cc
+++ b/chrome/browser/policy/configuration_policy_provider.cc
@@ -1,46 +1,13 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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 "chrome/browser/policy/configuration_policy_provider.h"
 
-#include <algorithm>
-
 #include "base/values.h"
 
 namespace policy {
 
-ConfigurationPolicyObserverRegistrar::ConfigurationPolicyObserverRegistrar() {}
-
-ConfigurationPolicyObserverRegistrar::~ConfigurationPolicyObserverRegistrar() {
-  RemoveAll();
-}
-
-void ConfigurationPolicyObserverRegistrar::Init(
-    ConfigurationPolicyProvider* provider) {
-  provider_ = provider;
-}
-
-void ConfigurationPolicyObserverRegistrar::AddObserver(
-    ConfigurationPolicyProvider::Observer* observer) {
-  observers_.push_back(observer);
-  provider_->AddObserver(observer);
-}
-
-void ConfigurationPolicyObserverRegistrar::RemoveObserver(
-    ConfigurationPolicyProvider::Observer* observer) {
-  std::remove(observers_.begin(), observers_.end(), observer);
-  provider_->RemoveObserver(observer);
-}
-
-void ConfigurationPolicyObserverRegistrar::RemoveAll() {
-  for (std::vector<ConfigurationPolicyProvider::Observer*>::iterator it =
-       observers_.begin(); it != observers_.end(); ++it) {
-    provider_->RemoveObserver(*it);
-  }
-  observers_.clear();
-}
-
 // Class ConfigurationPolicyProvider.
 
 ConfigurationPolicyProvider::ConfigurationPolicyProvider(
@@ -65,4 +32,31 @@ void ConfigurationPolicyProvider::DecodePolicyValueTree(
   // supports it.
 }
 
+// Class ConfigurationPolicyObserverRegistrar.
+
+ConfigurationPolicyObserverRegistrar::ConfigurationPolicyObserverRegistrar() {}
+
+ConfigurationPolicyObserverRegistrar::~ConfigurationPolicyObserverRegistrar() {
+  if (provider_)
+    provider_->RemoveObserver(this);
+}
+
+void ConfigurationPolicyObserverRegistrar::Init(
+    ConfigurationPolicyProvider* provider,
+    ConfigurationPolicyProvider::Observer* observer) {
+  provider_ = provider;
+  observer_ = observer;
+  provider_->AddObserver(this);
+}
+
+void ConfigurationPolicyObserverRegistrar::OnUpdatePolicy() {
+  observer_->OnUpdatePolicy();
+}
+
+void ConfigurationPolicyObserverRegistrar::OnProviderGoingAway() {
+  observer_->OnProviderGoingAway();
+  provider_->RemoveObserver(this);
+  provider_ = NULL;
+}
+
 }  // namespace policy
diff --git a/chrome/browser/policy/configuration_policy_provider.h b/chrome/browser/policy/configuration_policy_provider.h
index 5639235..81c1813 100644
--- a/chrome/browser/policy/configuration_policy_provider.h
+++ b/chrome/browser/policy/configuration_policy_provider.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -7,7 +7,6 @@
 #pragma once
 
 #include <string>
-#include <vector>
 
 #include "base/basictypes.h"
 #include "base/scoped_ptr.h"
@@ -25,6 +24,7 @@ class ConfigurationPolicyProvider {
    public:
     virtual ~Observer() {}
     virtual void OnUpdatePolicy() = 0;
+    virtual void OnProviderGoingAway() = 0;
   };
 
   // Used for static arrays of policy values that is used to initialize an
@@ -83,17 +83,25 @@ class ConfigurationPolicyProvider {
 
 // Manages observers for a ConfigurationPolicyProvider. Is used to register
 // observers, and automatically removes them upon destruction.
-class ConfigurationPolicyObserverRegistrar {
+// Implementation detail: to avoid duplicate bookkeeping of registered
+// observers, this registrar class acts as a proxy for notifications (since it
+// needs to register itself anyway to get OnProviderGoingAway notifications).
+class ConfigurationPolicyObserverRegistrar
+    : ConfigurationPolicyProvider::Observer {
  public:
   ConfigurationPolicyObserverRegistrar();
   ~ConfigurationPolicyObserverRegistrar();
-  void Init(ConfigurationPolicyProvider* provider);
-  void AddObserver(ConfigurationPolicyProvider::Observer* observer);
-  void RemoveObserver(ConfigurationPolicyProvider::Observer* observer);
-  void RemoveAll();
+  void Init(ConfigurationPolicyProvider* provider,
+            ConfigurationPolicyProvider::Observer* observer);
+
+  // ConfigurationPolicyProvider::Observer implementation:
+  virtual void OnUpdatePolicy();
+  virtual void OnProviderGoingAway();
+
  private:
   ConfigurationPolicyProvider* provider_;
-  std::vector<ConfigurationPolicyProvider::Observer*> observers_;
+  ConfigurationPolicyProvider::Observer* observer_;
+
   DISALLOW_COPY_AND_ASSIGN(ConfigurationPolicyObserverRegistrar);
 };
 
diff --git a/chrome/browser/policy/configuration_policy_provider_keeper.cc b/chrome/browser/policy/configuration_policy_provider_keeper.cc
new file mode 100644
index 0000000..768bb93
--- /dev/null
+++ b/chrome/browser/policy/configuration_policy_provider_keeper.cc
@@ -0,0 +1,98 @@
+// Copyright (c) 2011 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 "chrome/browser/policy/configuration_policy_provider_keeper.h"
+
+#include "base/path_service.h"
+#include "chrome/browser/policy/configuration_policy_pref_store.h"
+#include "chrome/browser/policy/configuration_policy_provider.h"
+#if defined(OS_WIN)
+#include "chrome/browser/policy/configuration_policy_provider_win.h"
+#elif defined(OS_MACOSX)
+#include "chrome/browser/policy/configuration_policy_provider_mac.h"
+#elif defined(OS_POSIX)
+#include "chrome/browser/policy/config_dir_policy_provider.h"
+#endif
+#include "chrome/browser/policy/dummy_configuration_policy_provider.h"
+#include "chrome/common/chrome_paths.h"
+
+namespace policy {
+
+ConfigurationPolicyProviderKeeper::ConfigurationPolicyProviderKeeper()
+    : managed_platform_provider_(CreateManagedPlatformProvider()),
+      device_management_provider_(CreateDeviceManagementProvider()),
+      recommended_provider_(CreateRecommendedProvider()) {
+}
+
+ConfigurationPolicyProviderKeeper::ConfigurationPolicyProviderKeeper(
+    ConfigurationPolicyProvider* managed_platform_provider,
+    ConfigurationPolicyProvider* device_management_provider,
+    ConfigurationPolicyProvider* recommended_provider)
+    : managed_platform_provider_(managed_platform_provider),
+      device_management_provider_(device_management_provider),
+      recommended_provider_(recommended_provider) {
+}
+
+ConfigurationPolicyProvider*
+    ConfigurationPolicyProviderKeeper::managed_platform_provider() const {
+  return managed_platform_provider_.get();
+}
+
+ConfigurationPolicyProvider*
+    ConfigurationPolicyProviderKeeper::device_management_provider() const {
+  return device_management_provider_.get();
+}
+
+ConfigurationPolicyProvider*
+    ConfigurationPolicyProviderKeeper::recommended_provider() const {
+  return recommended_provider_.get();
+}
+
+ConfigurationPolicyProvider*
+    ConfigurationPolicyProviderKeeper::CreateManagedPlatformProvider() {
+  const ConfigurationPolicyProvider::PolicyDefinitionList* policy_list =
+      ConfigurationPolicyPrefStore::GetChromePolicyDefinitionList();
+#if defined(OS_WIN)
+  return new ConfigurationPolicyProviderWin(policy_list);
+#elif defined(OS_MACOSX)
+  return new ConfigurationPolicyProviderMac(policy_list);
+#elif defined(OS_POSIX)
+  FilePath config_dir_path;
+  if (PathService::Get(chrome::DIR_POLICY_FILES, &config_dir_path)) {
+    return new ConfigDirPolicyProvider(
+        policy_list,
+        config_dir_path.Append(FILE_PATH_LITERAL("managed")));
+  } else {
+    return new DummyConfigurationPolicyProvider(policy_list);
+  }
+#else
+  return new DummyConfigurationPolicyProvider(policy_list);
+#endif
+}
+
+ConfigurationPolicyProvider*
+    ConfigurationPolicyProviderKeeper::CreateDeviceManagementProvider() {
+  return new DummyConfigurationPolicyProvider(
+      ConfigurationPolicyPrefStore::GetChromePolicyDefinitionList());
+}
+
+ConfigurationPolicyProvider*
+    ConfigurationPolicyProviderKeeper::CreateRecommendedProvider() {
+  const ConfigurationPolicyProvider::PolicyDefinitionList* policy_list =
+      ConfigurationPolicyPrefStore::GetChromePolicyDefinitionList();
+#if defined(OS_POSIX) && !defined(OS_MACOSX)
+  FilePath config_dir_path;
+  if (PathService::Get(chrome::DIR_POLICY_FILES, &config_dir_path)) {
+    return new ConfigDirPolicyProvider(
+        policy_list,
+        config_dir_path.Append(FILE_PATH_LITERAL("recommended")));
+  } else {
+    return new DummyConfigurationPolicyProvider(policy_list);
+  }
+#else
+  return new DummyConfigurationPolicyProvider(policy_list);
+#endif
+}
+
+}  // namespace
diff --git a/chrome/browser/policy/configuration_policy_provider_keeper.h b/chrome/browser/policy/configuration_policy_provider_keeper.h
new file mode 100644
index 0000000..6994de4
--- /dev/null
+++ b/chrome/browser/policy/configuration_policy_provider_keeper.h
@@ -0,0 +1,46 @@
+// Copyright (c) 2011 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.
+
+#ifndef CHROME_BROWSER_POLICY_CONFIGURATION_POLICY_PROVIDER_KEEPER_H_
+#define CHROME_BROWSER_POLICY_CONFIGURATION_POLICY_PROVIDER_KEEPER_H_
+#pragma once
+
+#include "base/scoped_ptr.h"
+#include "chrome/browser/policy/configuration_policy_provider.h"
+
+namespace policy {
+
+// Manages the lifecycle of the shared platform-specific policy providers for
+// managed platform, device management and recommended policy.
+class ConfigurationPolicyProviderKeeper {
+ public:
+  ConfigurationPolicyProviderKeeper();
+  // Tests can pass in their own (dummy) providers using this c'tor.
+  ConfigurationPolicyProviderKeeper(
+      ConfigurationPolicyProvider* managed_platform_provider,
+      ConfigurationPolicyProvider* device_management_provider,
+      ConfigurationPolicyProvider* recommended_provider);
+  virtual ~ConfigurationPolicyProviderKeeper() {}
+
+  ConfigurationPolicyProvider* managed_platform_provider() const;
+
+  ConfigurationPolicyProvider* device_management_provider() const;
+
+  ConfigurationPolicyProvider* recommended_provider() const;
+
+ private:
+  scoped_ptr<ConfigurationPolicyProvider> managed_platform_provider_;
+  scoped_ptr<ConfigurationPolicyProvider> device_management_provider_;
+  scoped_ptr<ConfigurationPolicyProvider> recommended_provider_;
+
+  static ConfigurationPolicyProvider* CreateManagedPlatformProvider();
+  static ConfigurationPolicyProvider* CreateDeviceManagementProvider();
+  static ConfigurationPolicyProvider* CreateRecommendedProvider();
+
+  DISALLOW_COPY_AND_ASSIGN(ConfigurationPolicyProviderKeeper);
+};
+
+}  // namespace policy
+
+#endif  // CHROME_BROWSER_POLICY_CONFIGURATION_POLICY_PROVIDER_KEEPER_H_
diff --git a/chrome/browser/policy/device_management_policy_provider.cc b/chrome/browser/policy/device_management_policy_provider.cc
index 1a1f0c2..8b9d9b4 100644
--- a/chrome/browser/policy/device_management_policy_provider.cc
+++ b/chrome/browser/policy/device_management_policy_provider.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -108,7 +108,11 @@ DeviceManagementPolicyProvider::DeviceManagementPolicyProvider(
              unmanaged_device_refresh_rate_ms);
 }
 
-DeviceManagementPolicyProvider::~DeviceManagementPolicyProvider() {}
+DeviceManagementPolicyProvider::~DeviceManagementPolicyProvider() {
+  FOR_EACH_OBSERVER(ConfigurationPolicyProvider::Observer,
+                    observer_list_,
+                    OnProviderGoingAway());
+}
 
 bool DeviceManagementPolicyProvider::Provide(
     ConfigurationPolicyStoreInterface* policy_store) {
@@ -183,12 +187,6 @@ void DeviceManagementPolicyProvider::OnNotManaged() {
   StopWaitingForInitialPolicies();
 }
 
-void DeviceManagementPolicyProvider::Shutdown() {
-  profile_ = NULL;
-  if (token_fetcher_)
-    token_fetcher_->Shutdown();
-}
-
 void DeviceManagementPolicyProvider::AddObserver(
     ConfigurationPolicyProvider::Observer* observer) {
   observer_list_.AddObserver(observer);
diff --git a/chrome/browser/policy/device_management_policy_provider.h b/chrome/browser/policy/device_management_policy_provider.h
index 17edf82..fd18bc3 100644
--- a/chrome/browser/policy/device_management_policy_provider.h
+++ b/chrome/browser/policy/device_management_policy_provider.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -54,10 +54,6 @@ class DeviceManagementPolicyProvider
   virtual void OnTokenError();
   virtual void OnNotManaged();
 
-  // Tells the provider that the passed in token service reference is about to
-  // become invalid.
-  void Shutdown();
-
  private:
   class InitializeAfterIOThreadExistsTask;
   class RefreshTask;
diff --git a/chrome/browser/policy/device_management_policy_provider_unittest.cc b/chrome/browser/policy/device_management_policy_provider_unittest.cc
index 4886f9d..eac2c5b 100644
--- a/chrome/browser/policy/device_management_policy_provider_unittest.cc
+++ b/chrome/browser/policy/device_management_policy_provider_unittest.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -34,6 +34,7 @@ class MockConfigurationPolicyObserver
     : public ConfigurationPolicyProvider::Observer {
  public:
   MOCK_METHOD0(OnUpdatePolicy, void());
+  void OnProviderGoingAway() {}
 };
 
 class DeviceManagementPolicyProviderTest : public testing::Test {
@@ -207,8 +208,7 @@ TEST_F(DeviceManagementPolicyProviderTest, SecondProvide) {
 TEST_F(DeviceManagementPolicyProviderTest, FetchTriggersRefresh) {
   MockConfigurationPolicyObserver observer;
   ConfigurationPolicyObserverRegistrar registrar;
-  registrar.Init(provider_.get());
-  registrar.AddObserver(&observer);
+  registrar.Init(provider_.get(), &observer);
   EXPECT_CALL(observer, OnUpdatePolicy()).Times(1);
   SimulateSuccessfulInitialPolicyFetch();
 }
diff --git a/chrome/browser/policy/device_token_fetcher.cc b/chrome/browser/policy/device_token_fetcher.cc
index 678c90f..2d514b6 100644
--- a/chrome/browser/policy/device_token_fetcher.cc
+++ b/chrome/browser/policy/device_token_fetcher.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -212,11 +212,6 @@ void DeviceTokenFetcher::StartFetching() {
   }
 }
 
-void DeviceTokenFetcher::Shutdown() {
-  profile_ = NULL;
-  backend_ = NULL;
-}
-
 void DeviceTokenFetcher::AttemptTokenLoadFromDisk() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
   if (file_util::PathExists(token_path_)) {
diff --git a/chrome/browser/policy/device_token_fetcher.h b/chrome/browser/policy/device_token_fetcher.h
index f047e61..ae22f3d 100644
--- a/chrome/browser/policy/device_token_fetcher.h
+++ b/chrome/browser/policy/device_token_fetcher.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -79,10 +79,6 @@ class DeviceTokenFetcher
   // will need the token in the future. Must be called on the UI thread.
   void StartFetching();
 
-  // Instructs the fetcher to shut down, before the backend and token service
-  // references become stale.
-  void Shutdown();
-
   // Returns true if there is a pending token request to the device management
   // server.
   bool IsTokenPending();
diff --git a/chrome/browser/policy/dummy_configuration_policy_provider.cc b/chrome/browser/policy/dummy_configuration_policy_provider.cc
index 9a8f491..973ee4c 100644
--- a/chrome/browser/policy/dummy_configuration_policy_provider.cc
+++ b/chrome/browser/policy/dummy_configuration_policy_provider.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -12,6 +12,9 @@ DummyConfigurationPolicyProvider::DummyConfigurationPolicyProvider(
 }
 
 DummyConfigurationPolicyProvider::~DummyConfigurationPolicyProvider() {
+  FOR_EACH_OBSERVER(ConfigurationPolicyProvider::Observer,
+                    observer_list_,
+                    OnProviderGoingAway());
 }
 
 bool DummyConfigurationPolicyProvider::Provide(
@@ -19,4 +22,14 @@ bool DummyConfigurationPolicyProvider::Provide(
   return true;
 }
 
+void DummyConfigurationPolicyProvider::AddObserver(
+    ConfigurationPolicyProvider::Observer* observer) {
+  observer_list_.AddObserver(observer);
+}
+
+void DummyConfigurationPolicyProvider::RemoveObserver(
+    ConfigurationPolicyProvider::Observer* observer) {
+  observer_list_.RemoveObserver(observer);
+}
+
 }  // namespace policy
diff --git a/chrome/browser/policy/dummy_configuration_policy_provider.h b/chrome/browser/policy/dummy_configuration_policy_provider.h
index 22ca152..119a74b 100644
--- a/chrome/browser/policy/dummy_configuration_policy_provider.h
+++ b/chrome/browser/policy/dummy_configuration_policy_provider.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_POLICY_DUMMY_CONFIGURATION_POLICY_PROVIDER_H_
 #pragma once
 
+#include "base/observer_list.h"
 #include "chrome/browser/policy/configuration_policy_provider.h"
 
 namespace policy {
@@ -22,9 +23,10 @@ class DummyConfigurationPolicyProvider : public ConfigurationPolicyProvider {
 
  private:
   // ConfigurationPolicyProvider overrides:
-  virtual void AddObserver(ConfigurationPolicyProvider::Observer* observer) {}
-  virtual void RemoveObserver(
-      ConfigurationPolicyProvider::Observer* observer) {}
+  virtual void AddObserver(ConfigurationPolicyProvider::Observer* observer);
+  virtual void RemoveObserver(ConfigurationPolicyProvider::Observer* observer);
+
+  ObserverList<ConfigurationPolicyProvider::Observer, true> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(DummyConfigurationPolicyProvider);
 };
diff --git a/chrome/browser/policy/profile_policy_context.cc b/chrome/browser/policy/profile_policy_context.cc
index c4b6e5b..c221529 100644
--- a/chrome/browser/policy/profile_policy_context.cc
+++ b/chrome/browser/policy/profile_policy_context.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -39,8 +39,6 @@ void ProfilePolicyContext::Initialize() {
 void ProfilePolicyContext::Shutdown() {
   if (device_management_service_.get())
     device_management_service_->Shutdown();
-  if (device_management_policy_provider_.get())
-    device_management_policy_provider_->Shutdown();
 }
 
 DeviceManagementPolicyProvider*