Remove the last usages of PrefObserver outside of Prefs.

base/prefs/public/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 "base/prefs/public/pref_change_registrar.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/prefs/public/pref_service_base.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(PrefServiceBase* service) {
   DCHECK(IsEmpty() || service_ == service);
   service_ = service;
 }
 
-void PrefChangeRegistrar::Add(const char* path, PrefObserver* obs) {
-  DCHECK(obs);
-  return Add(path, base::Bind(&PrefObserver::OnPreferenceChanged,
-                              base::Unretained(obs), service_));
-}
-
 void PrefChangeRegistrar::Add(const char* path,
                               const base::Closure& obs) {
   Add(path, base::Bind(&PrefChangeRegistrar::InvokeUnnamedCallback, obs));
 }
 
 void PrefChangeRegistrar::Add(const char* path,
                               const NamedChangeCallback& obs) {
   if (!service_) {
     NOTREACHED();
     return;
@@ skipping 46 matching lines @@
 }
 
 void PrefChangeRegistrar::InvokeUnnamedCallback(const base::Closure& callback,
                                                 const std::string& pref_name) {
   callback.Run();
 }
 
 PrefServiceBase* PrefChangeRegistrar::prefs() {
   return service_;
 }