WIP

chrome/browser/policy/policy_change_watcher.h

Index: chrome/browser/policy/policy_change_watcher.h
diff --git a/chrome/browser/policy/policy_change_watcher.h b/chrome/browser/policy/policy_change_watcher.h
new file mode 100644
index 0000000000000000000000000000000000000000..024023848d920a5dba37363221543f61b758052e
--- /dev/null
+++ b/chrome/browser/policy/policy_change_watcher.h
@@ -0,0 +1,106 @@
+// Copyright (c) 2013 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_POLICY_CHANGE_WATCHER_H_
+#define CHROME_BROWSER_POLICY_POLICY_CHANGE_WATCHER_H_
+
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/observer_list.h"
+#include "chrome/browser/policy/policy_bundle.h"
+#include "chrome/browser/policy/policy_service.h"
+
+class PrefRegistrySimple;
+class PrefRegistrySyncable;
+class Profile;
+
+namespace policy {
+
+class PolicyServiceChangeWatcher : public PolicyService::Observer {
+ public:
+  PolicyServiceChangeWatcher(PolicyService* policy_service,
+                             const std::string& current_hash);
+  virtual ~PolicyServiceChangeWatcher();
+
+  // PolicyService::Observer:
+  virtual void OnPolicyUpdated(const PolicyNamespace& ns,
+                               const PolicyMap& previous,
+                               const PolicyMap& current) OVERRIDE;
+  virtual void OnPolicyServiceInitialized(PolicyDomain domain) OVERRIDE;
+
+ protected:
+  bool is_initialization_complete() const {
+      return !domains_pending_initialization_;
+  }
+
+  const std::string& current_hash() const { return current_hash_; };
+
+  virtual void Init();
+
+  virtual void OnPolicyChanged() = 0;
+
+ private:
+  void CheckIfPolicyChanged(const PolicyBundle& bundle);
+
+  int domains_pending_initialization_;
+  std::string current_hash_;
+
+  PolicyService* policy_service_;
+
+  DISALLOW_COPY_AND_ASSIGN(PolicyServiceChangeWatcher);
+};
+
+class DevicePolicyChangeWatcher : public PolicyServiceChangeWatcher {
+ public:
+  class Observer {
+   public:
+    virtual void OnDevicePolicyStatusChanged(
+        const std::vector<std::string>& users_with_changed_device_policy) = 0;
+
+   protected:
+    virtual ~Observer();
+  };
+
+  DevicePolicyChangeWatcher();
+  virtual ~DevicePolicyChangeWatcher();
+
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+  static void RegisterPrefs(PrefRegistrySimple* registry);
+
+  void AcknowledgePolicyChange(const std::string& username);
+
+ private:
+  std::vector<std::string> ListUsersWithChangedDevicePolicy() const;
+  void NotifyDevicePolicyStatusChanged();
+
+  // PolicyServiceChangeWatcher:
+  virtual void OnPolicyChanged() OVERRIDE;
+
+  ObserverList<Observer, true> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(DevicePolicyChangeWatcher);
+};
+
+class UserPolicyChangeWatcher : public PolicyServiceChangeWatcher {
+ public:
+  UserPolicyChangeWatcher(Profile* profile);
+  virtual ~UserPolicyChangeWatcher();
+
+  static void RegisterUserPrefs(PrefRegistrySyncable* registry);
+
+ private:
+  // PolicyServiceChangeWatcher:
+  virtual void OnPolicyChanged() OVERRIDE;
+
+  DISALLOW_COPY_AND_ASSIGN(UserPolicyChangeWatcher);
+};
+
+}  // namespace policy
+
+#endif  // CHROME_BROWSER_POLICY_POLICY_CHANGE_WATCHER_H_