Revert 170483 - Remove PrefObserver usages, batch 12.

chrome/browser/ui/cocoa/location_bar/location_bar_view_mac.mm

 // Copyright 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.
 
 #import "chrome/browser/ui/cocoa/location_bar/location_bar_view_mac.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/stl_util.h"
@@ skipping 121 matching lines @@
       rb.GetNativeImageNamed(IDR_OMNIBOX_WI_BUBBLE_BACKGROUND_C).ToNSImage(),
       rb.GetNativeImageNamed(IDR_OMNIBOX_WI_BUBBLE_BACKGROUND_R).ToNSImage());
 
   registrar_.Add(this,
       chrome::NOTIFICATION_EXTENSION_PAGE_ACTION_VISIBILITY_CHANGED,
       content::NotificationService::AllSources());
   registrar_.Add(this,
       chrome::NOTIFICATION_EXTENSION_LOCATION_BAR_UPDATED,
       content::Source<Profile>(browser_->profile()));
 
-  edit_bookmarks_enabled_.Init(
-      prefs::kEditBookmarksEnabled,
-      profile_->GetPrefs(),
-      base::Bind(&LocationBarViewMac::OnEditBookmarksEnabledChanged,
-                 base::Unretained(this)));
+  edit_bookmarks_enabled_.Init(prefs::kEditBookmarksEnabled,
+                               profile_->GetPrefs(), this);
 }
 
 LocationBarViewMac::~LocationBarViewMac() {
   // Disconnect from cell in case it outlives us.
   [[field_ cell] clearDecorations];
 }
 
 void LocationBarViewMac::ShowFirstRunBubble() {
   // We need the browser window to be shown before we can show the bubble, but
   // we get called before that's happened.
@@ skipping 436 matching lines @@
         UpdatePageActions();
       break;
     }
 
     default:
       NOTREACHED() << "Unexpected notification";
       break;
   }
 }
 
-void LocationBarViewMac::OnEditBookmarksEnabledChanged() {
+void LocationBarViewMac::OnPreferenceChanged(PrefServiceBase* service,
+                                             const std::string& pref_name) {
   UpdateStarDecorationVisibility();
   OnChanged();
 }
 
 void LocationBarViewMac::PostNotification(NSString* notification) {
   [[NSNotificationCenter defaultCenter] postNotificationName:notification
                                         object:[NSValue valueWithPointer:this]];
 }
 
 bool LocationBarViewMac::RefreshContentSettingsDecorations() {
@@ skipping 165 matching lines @@
     visible = false;
   star_decoration_->SetVisible(visible);
 }
 
 void LocationBarViewMac::UpdatePlusDecorationVisibility() {
   if (extensions::FeatureSwitch::action_box()->IsEnabled()) {
     // If the action box is enabled, hide it when input is in progress.
     plus_decoration_->SetVisible(!toolbar_model_->GetInputInProgress());
   }
 }