Added Protector backup for Preferences.

chrome/browser/protector/protected_prefs_watcher.h

Index: chrome/browser/protector/protected_prefs_watcher.h
diff --git a/chrome/browser/protector/protected_prefs_watcher.h b/chrome/browser/protector/protected_prefs_watcher.h
new file mode 100644
index 0000000000000000000000000000000000000000..cc2b95755c53298464fc20538e488dd6a00f02fd
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+++ b/chrome/browser/protector/protected_prefs_watcher.h
@@ -0,0 +1,80 @@
+// 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.
+
+#ifndef CHROME_BROWSER_PROTECTOR_PROTECTED_PREFS_WATCHER_H_
+#define CHROME_BROWSER_PROTECTOR_PROTECTED_PREFS_WATCHER_H_
+#pragma once
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "chrome/browser/extensions/extension_prefs.h"
+#include "content/public/browser/notification_observer.h"
+
+class PrefService;
+class PrefSetObserver;
+class Profile;
+
+namespace base {
+class Value;
+}
+
+namespace protector {
+
+class ProtectedPrefsWatcher : public content::NotificationObserver {
+ public:
+  explicit ProtectedPrefsWatcher(Profile* profile);
+  ~ProtectedPrefsWatcher();
+
+  // Registers prefs on a new Profile instance.
+  static void RegisterUserPrefs(PrefService* prefs);
+
+  // Perform a check that backup is valid and settings have not been modified.
+  // TODO(ivankr): currently this is a stub that simply updates the backup.
+  void ValidatePrefs();
+
+  // Returns the backup value for pref named |path| or |NULL| if the pref is
+  // not protected or does not exist. The returned Value instance is owned by
+  // the PrefService.
+  const base::Value* GetBackupForPref(const std::string& path) const;
+
+  // Returns |true| if backup signature is valid.
+  bool IsSignatureValid() const;
+
+  // Returns |false| if profile does not have a backup yet (needs to be
+  // initialized).
+  bool HasBackup() const;
+
+ private:
+  // content::NotificationObserver overrides:
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+  // Updates cached prefs from their actual values and returns |true| if there
+  // were any changes.
+  bool UpdateCachedPrefs();
+
+  // Update the backup signature.
+  void UpdateBackupSignature();
+
+  // Returns data to be signed as string.
+  std::string GetSignatureData(PrefService* prefs) const;
+
+  // Cached set of extension IDs. They are not changed as frequently
+  ExtensionPrefs::ExtensionIdSet cached_extension_ids_;
+
+  scoped_ptr<PrefSetObserver> pref_observer_;
+
+  bool did_startup_settings_change_;
+
+  Profile* profile_;
+
+  DISALLOW_COPY_AND_ASSIGN(ProtectedPrefsWatcher);
+};
+
+}  // namespace protector
+
+#endif  // CHROME_BROWSER_PROTECTOR_PROTECTED_PREFS_WATCHER_H_