Remove stl_util's STLDeleteContainerPairSecondPointers from prefs.

components/prefs/pref_notifier_impl.cc

 // 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.
 
 #include "components/prefs/pref_notifier_impl.h"
 
 #include "base/logging.h"
-#include "base/stl_util.h"
+#include "base/memory/ptr_util.h"
 #include "components/prefs/pref_service.h"
 
-PrefNotifierImpl::PrefNotifierImpl()
-    : pref_service_(NULL) {
-}
+PrefNotifierImpl::PrefNotifierImpl() : pref_service_(nullptr) {}
 
 PrefNotifierImpl::PrefNotifierImpl(PrefService* service)
     : pref_service_(service) {
 }
 
 PrefNotifierImpl::~PrefNotifierImpl() {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   // Verify that there are no pref observers when we shut down.
-  for (PrefObserverMap::iterator it = pref_observers_.begin();
-       it != pref_observers_.end(); ++it) {
-    PrefObserverList::Iterator obs_iterator(it->second);
+  for (const auto& observer_list : pref_observers_) {
+    PrefObserverList::Iterator obs_iterator(observer_list.second.get());
     if (obs_iterator.GetNext()) {
-      LOG(WARNING) << "pref observer found at shutdown " << it->first;
+      LOG(WARNING) << "Pref observer found at shutdown.";
     }
   }
 
   // Same for initialization observers.
   if (!init_observers_.empty())
     LOG(WARNING) << "Init observer found at shutdown.";
 
-  base::STLDeleteContainerPairSecondPointers(pref_observers_.begin(),
-                                             pref_observers_.end());
   pref_observers_.clear();
   init_observers_.clear();
 }
 
 void PrefNotifierImpl::AddPrefObserver(const std::string& path,
                                        PrefObserver* obs) {
   // Get the pref observer list associated with the path.
-  PrefObserverList* observer_list = NULL;
-  const PrefObserverMap::iterator observer_iterator =
-      pref_observers_.find(path);
+  PrefObserverList* observer_list = nullptr;
+  auto observer_iterator = pref_observers_.find(path);
   if (observer_iterator == pref_observers_.end()) {
     observer_list = new PrefObserverList;
-    pref_observers_[path] = observer_list;
+    pref_observers_[path] = base::WrapUnique(observer_list);
   } else {
-    observer_list = observer_iterator->second;
+    observer_list = observer_iterator->second.get();
   }
 
   // Add the pref observer. ObserverList will DCHECK if it already is
   // in the list.
   observer_list->AddObserver(obs);
 }
 
 void PrefNotifierImpl::RemovePrefObserver(const std::string& path,
                                           PrefObserver* obs) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
-  const PrefObserverMap::iterator observer_iterator =
-      pref_observers_.find(path);
+  auto observer_iterator = pref_observers_.find(path);
   if (observer_iterator == pref_observers_.end()) {
     return;
   }
 
-  PrefObserverList* observer_list = observer_iterator->second;
+  PrefObserverList* observer_list = observer_iterator->second.get();
   observer_list->RemoveObserver(obs);
 }
 
 void PrefNotifierImpl::AddInitObserver(base::Callback<void(bool)> obs) {
   init_observers_.push_back(obs);
 }
 
 void PrefNotifierImpl::OnPreferenceChanged(const std::string& path) {
   FireObservers(path);
 }
 
 void PrefNotifierImpl::OnInitializationCompleted(bool succeeded) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   // We must make a copy of init_observers_ and clear it before we run
   // observers, or we can end up in this method re-entrantly before
   // clearing the observers list.
   PrefInitObserverList observers(init_observers_);
   init_observers_.clear();
 
-  for (PrefInitObserverList::iterator it = observers.begin();
-       it != observers.end();
-       ++it) {
-    it->Run(succeeded);
-  }
+  for (auto& observer : observers)
+    observer.Run(succeeded);
 }
 
 void PrefNotifierImpl::FireObservers(const std::string& path) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   // Only send notifications for registered preferences.
   if (!pref_service_->FindPreference(path))
     return;
 
-  const PrefObserverMap::iterator observer_iterator =
-      pref_observers_.find(path);
+  auto observer_iterator = pref_observers_.find(path);
   if (observer_iterator == pref_observers_.end())
     return;
 
   FOR_EACH_OBSERVER(PrefObserver,
                     *(observer_iterator->second),
                     OnPreferenceChanged(pref_service_, path));
 }
 
 void PrefNotifierImpl::SetPrefService(PrefService* pref_service) {
-  DCHECK(pref_service_ == NULL);
+  DCHECK(pref_service_ == nullptr);
   pref_service_ = pref_service;
 }