Move preference MACs to the protected preference stores.

chrome/browser/prefs/tracked/pref_store_hash_store_contents.h

+// Copyright 2014 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_PREFS_TRACKED_PREF_STORE_HASH_STORE_CONTENTS_H_
+#define CHROME_BROWSER_PREFS_TRACKED_PREF_STORE_HASH_STORE_CONTENTS_H_
+
+#include <string>
+#include "base/compiler_specific.h"
+#include "base/macros.h"
+#include "chrome/browser/prefs/tracked/hash_store_contents.h"
+
+namespace user_prefs {
+class PrefRegistrySyncable;
+}  // namespace user_prefs
+
+class PersistentPrefStore;
+class WriteablePrefStore;
+
+class PrefStoreHashStoreContents : public HashStoreContents {
+ public:
+  // A super MAC used to validate the hash store contents when determining
+  // whether
+  // an unknown value is to be trusted is stored as a string under
+  // |kSuperMacPref|
+  static const char kSuperMacPref[];
+
+  // Does not increment the reference count on |pref_store|. Assumes that
+  // |pref_store| indirectly owns this HashStoreContents.
+  explicit PrefStoreHashStoreContents(PersistentPrefStore* pref_store);
+
+  // Does not increment the reference count on |pref_store|. Assumes that
+  // |pref_store| indirectly owns this HashStoreContents. Ignores calls to
+  // CommitPendingWrite() because this is not supported by the (presumably
+  // in-memory) WriteablePrefStore.
+  explicit PrefStoreHashStoreContents(WriteablePrefStore* pref_store);
+
+  // Registers required preferences.
+  static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
+
+  // HashStoreContents implementation
+  virtual std::string hash_store_id() const OVERRIDE;
+  virtual void Reset() OVERRIDE;
+  virtual bool IsInitialized() const OVERRIDE;
+  virtual const base::DictionaryValue* GetContents() const OVERRIDE;
+  virtual scoped_ptr<MutableDictionary> GetMutableContents() OVERRIDE;
+  virtual std::string GetSuperMac() const OVERRIDE;
+  virtual void SetSuperMac(const std::string& super_mac) OVERRIDE;
+  virtual void CommitPendingWrite() OVERRIDE;
+
+ private:
+  WriteablePrefStore* const pref_store_;
+  PersistentPrefStore* const persistent_pref_store_;
+
+  DISALLOW_COPY_AND_ASSIGN(PrefStoreHashStoreContents);
+};
+
+#endif  // CHROME_BROWSER_PREFS_TRACKED_PREF_STORE_HASH_STORE_CONTENTS_H_