Remove PrefObserver usage, batch 9.

chrome/browser/net/net_pref_observer.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 "chrome/browser/net/net_pref_observer.h"
 
 #include "chrome/browser/net/predictor.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/prerender/prerender_manager.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
 #include "net/http/http_stream_factory.h"
 
 using content::BrowserThread;
 
 NetPrefObserver::NetPrefObserver(PrefService* prefs,
                                  prerender::PrerenderManager* prerender_manager,
                                  chrome_browser_net::Predictor* predictor)
     : prerender_manager_(prerender_manager),
       predictor_(predictor) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(prefs);
   DCHECK(predictor);
 
+  base::Closure prefs_callback = base::Bind(&NetPrefObserver::ApplySettings,
+                                            base::Unretained(this));
   network_prediction_enabled_.Init(prefs::kNetworkPredictionEnabled, prefs,
-                                   this);
-  spdy_disabled_.Init(prefs::kDisableSpdy, prefs, this);
+                                   prefs_callback);
+  spdy_disabled_.Init(prefs::kDisableSpdy, prefs, prefs_callback);
 
   ApplySettings();
 }
 
 NetPrefObserver::~NetPrefObserver() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
 
-void NetPrefObserver::OnPreferenceChanged(PrefServiceBase* service,
-                                          const std::string& pref_name) {
-  ApplySettings();
-}
-
 void NetPrefObserver::ApplySettings() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   predictor_->EnablePredictor(*network_prediction_enabled_);
   if (prerender_manager_)
     prerender_manager_->set_enabled(*network_prediction_enabled_);
   if (spdy_disabled_.IsManaged())
     net::HttpStreamFactory::set_spdy_enabled(!*spdy_disabled_);
 }
 
 // static
 void NetPrefObserver::RegisterPrefs(PrefService* prefs) {
   prefs->RegisterBooleanPref(prefs::kNetworkPredictionEnabled,
                              true,
                              PrefService::SYNCABLE_PREF);
   prefs->RegisterBooleanPref(prefs::kDisableSpdy,
                              false,
                              PrefService::UNSYNCABLE_PREF);
 }