Remove JsonPrefStore pruning of empty values on write.

base/prefs/pref_service.h

 // 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.
 
 // This provides a way to access the application's current preferences.
 
 // Chromium settings and storage represent user-selected preferences and
 // information and MUST not be extracted, overwritten or modified except
 // through Chromium defined APIs.
 
@@ skipping 203 matching lines @@
   // Changes the default value for a preference. Takes ownership of |value|.
   //
   // Will cause a pref change notification to be fired if this causes
   // the effective value to change.
   void SetDefaultPrefValue(const char* path, base::Value* value);
 
   // Returns the default value of the given preference. |path| must point to a
   // registered preference. In that case, will never return NULL.
   const base::Value* GetDefaultPrefValue(const char* path) const;
 
-  // Deprecated. Do not add calls to this method.
-  // Marks that the user store should not prune out empty values for |key| when
-  // writting to disk.
-  // TODO(gab): Enforce this at a lower level for all values and remove this
-  // method.
-  void MarkUserStoreNeedsEmptyValue(const std::string& key) const;
-
   // Returns true if a value has been set for the specified path.
   // NOTE: this is NOT the same as FindPreference. In particular
   // FindPreference returns whether RegisterXXX has been invoked, where as
   // this checks if a value exists for the path.
   bool HasPrefPath(const char* path) const;
 
   // Returns a dictionary with effective preference values. The ownership
   // is passed to the caller.
   scoped_ptr<base::DictionaryValue> GetPreferenceValues() const;
 
@@ skipping 20 matching lines @@
   // parameter will be set to true for successful initialization,
   // false for unsuccessful.
   void AddPrefInitObserver(base::Callback<void(bool)> callback);
 
   // Returns the PrefRegistry object for this service. You should not
   // use this; the intent is for no registrations to take place after
   // PrefService has been constructed.
   PrefRegistry* DeprecatedGetPrefRegistry();
 
  protected:
-  // Adds the registered preferences from the PrefRegistry instance
-  // passed to us at construction time.
-  void AddInitialPreferences();
-
-  // Updates local caches for a preference registered at |path|. The
-  // |default_value| must not be NULL as it determines the preference
-  // value's type.  AddRegisteredPreference must not be called twice
-  // for the same path.
-  void AddRegisteredPreference(const char* path,
-                               base::Value* default_value);
-
   // The PrefNotifier handles registering and notifying preference observers.
   // It is created and owned by this PrefService. Subclasses may access it for
   // unit testing.
   scoped_ptr<PrefNotifierImpl> pref_notifier_;
 
   // The PrefValueStore provides prioritized preference values. It is owned by
   // this PrefService. Subclasses may access it for unit testing.
   scoped_ptr<PrefValueStore> pref_value_store_;
 
   scoped_refptr<PrefRegistry> pref_registry_;
@@ skipping 66 matching lines @@
 
   // Local cache of registered Preference objects. The pref_registry_
   // is authoritative with respect to what the types and default values
   // of registered preferences are.
   mutable PreferenceMap prefs_map_;
 
   DISALLOW_COPY_AND_ASSIGN(PrefService);
 };
 
 #endif  // BASE_PREFS_PREF_SERVICE_H_