Move PrefMember and PrefChangeRegistrar to api directory.

chrome/browser/prefs/pref_change_registrar.cc

-// Copyright (c) 2010 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/pref_change_registrar.h"
-
-#include "base/logging.h"
-#include "chrome/browser/prefs/pref_service.h"
-
-PrefChangeRegistrar::PrefChangeRegistrar() : service_(NULL) {}
-
-PrefChangeRegistrar::~PrefChangeRegistrar() {
-  // If you see an invalid memory access in this destructor, this
-  // PrefChangeRegistrar might be subscribed to an OffTheRecordProfileImpl that
-  // has been destroyed. This should not happen any more but be warned.
-  // Feel free to contact battre@chromium.org in case this happens.
-  RemoveAll();
-}
-
-void PrefChangeRegistrar::Init(PrefService* service) {
-  DCHECK(IsEmpty() || service_ == service);
-  service_ = service;
-}
-
-void PrefChangeRegistrar::Add(const char* path,
-                              content::NotificationObserver* obs) {
-  if (!service_) {
-    NOTREACHED();
-    return;
-  }
-  ObserverRegistration registration(path, obs);
-  if (observers_.find(registration) != observers_.end()) {
-    NOTREACHED();
-    return;
-  }
-  observers_.insert(registration);
-  service_->AddPrefObserver(path, obs);
-}
-
-void PrefChangeRegistrar::Remove(const char* path,
-                                 content::NotificationObserver* obs) {
-  if (!service_) {
-    NOTREACHED();
-    return;
-  }
-  ObserverRegistration registration(path, obs);
-  std::set<ObserverRegistration>::iterator it =
-       observers_.find(registration);
-  if (it == observers_.end()) {
-    NOTREACHED();
-    return;
-  }
-  service_->RemovePrefObserver(it->first.c_str(), it->second);
-  observers_.erase(it);
-}
-
-void PrefChangeRegistrar::RemoveAll() {
-  if (service_) {
-    for (std::set<ObserverRegistration>::const_iterator it = observers_.begin();
-         it != observers_.end(); ++it) {
-      service_->RemovePrefObserver(it->first.c_str(), it->second);
-    }
-    observers_.clear();
-  }
-}
-
-bool PrefChangeRegistrar::IsEmpty() const {
-  return observers_.empty();
-}