Componentize PrefSyncableService and support classes.

chrome/browser/prefs/synced_pref_change_registrar.cc

-// Copyright 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.
-
-#include "chrome/browser/prefs/synced_pref_change_registrar.h"
-
-#include "base/bind.h"
-
-namespace {
-
-void InvokeUnnamedCallback(
-    const SyncedPrefChangeRegistrar::ChangeCallback& callback,
-    const std::string& path,
-    bool from_sync) {
-  callback.Run(from_sync);
-}
-
-}  // namespace
-
-SyncedPrefChangeRegistrar::SyncedPrefChangeRegistrar(
-    PrefServiceSyncable* pref_service) {
-  pref_service_ = pref_service;
-}
-
-SyncedPrefChangeRegistrar::~SyncedPrefChangeRegistrar() {
-  RemoveAll();
-}
-
-void SyncedPrefChangeRegistrar::Add(const char *path,
-                                    const ChangeCallback& callback) {
-  Add(path, base::Bind(InvokeUnnamedCallback, callback));
-}
-
-void SyncedPrefChangeRegistrar::Add(const char *path,
-                                    const NamedChangeCallback& callback) {
-  DCHECK(!IsObserved(path));
-  observers_[path] = callback;
-  pref_service_->AddSyncedPrefObserver(path, this);
-}
-
-void SyncedPrefChangeRegistrar::Remove(const char *path) {
-  observers_.erase(path);
-  pref_service_->RemoveSyncedPrefObserver(path, this);
-}
-
-void SyncedPrefChangeRegistrar::RemoveAll() {
-  for (ObserverMap::iterator iter = observers_.begin();
-       iter != observers_.end(); ++iter) {
-    pref_service_->RemoveSyncedPrefObserver(iter->first, this);
-  }
-  observers_.clear();
-}
-
-bool SyncedPrefChangeRegistrar::IsObserved(const char* path) const {
-  return observers_.find(path) != observers_.end();
-}
-
-void SyncedPrefChangeRegistrar::OnSyncedPrefChanged(const std::string& path,
-                                                    bool from_sync) {
-  if (pref_service_->IsManagedPreference(path.c_str()))
-    return;
-  ObserverMap::const_iterator iter = observers_.find(path);
-  if (iter == observers_.end())
-    return;
-  iter->second.Run(path, from_sync);
-}