Revert 170483 - Remove PrefObserver usages, batch 12.

chrome/browser/ui/cocoa/browser_window_cocoa.mm

 // 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/ui/cocoa/browser_window_cocoa.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/mac/mac_util.h"
@@ skipping 71 matching lines @@
 
 BrowserWindowCocoa::BrowserWindowCocoa(Browser* browser,
                                        BrowserWindowController* controller)
   : browser_(browser),
     controller_(controller),
     confirm_close_factory_(browser),
     initial_show_state_(ui::SHOW_STATE_DEFAULT),
     attention_request_id_(0) {
 
   pref_change_registrar_.Init(browser_->profile()->GetPrefs());
-  pref_change_registrar_.Add(
-      prefs::kShowBookmarkBar,
-      base::Bind(&BrowserWindowCocoa::OnShowBookmarkBarChanged,
-                 base::Unretained(this)));
+  pref_change_registrar_.Add(prefs::kShowBookmarkBar, this);
   gfx::Rect bounds;
   chrome::GetSavedWindowBoundsAndShowState(browser_,
                                            &bounds,
                                            &initial_show_state_);
 }
 
 BrowserWindowCocoa::~BrowserWindowCocoa() {
 }
 
 void BrowserWindowCocoa::Show() {
@@ skipping 504 matching lines @@
   // BrowserWindow object.
   FindBarBridge* bridge = new FindBarBridge();
   AddFindBar(bridge->find_bar_cocoa_controller());
   return bridge;
 }
 
 bool BrowserWindowCocoa::GetConstrainedWindowTopY(int* top_y) {
   return false;
 }
 
-void BrowserWindowCocoa::OnShowBookmarkBarChanged() {
+void BrowserWindowCocoa::OnPreferenceChanged(PrefServiceBase* service,
+                                             const std::string& pref_name) {
+  DCHECK(pref_name == prefs::kShowBookmarkBar);
   [controller_ updateBookmarkBarVisibilityWithAnimation:YES];
 }
 
 extensions::ActiveTabPermissionGranter*
     BrowserWindowCocoa::GetActiveTabPermissionGranter() {
   TabContents* tab_contents =
       browser_->tab_strip_model()->GetActiveTabContents();
   if (!tab_contents)
     return NULL;
   extensions::TabHelper* tab_helper =
@@ skipping 27 matching lines @@
   AvatarMenuBubbleController* menu =
       [[AvatarMenuBubbleController alloc] initWithBrowser:browser_
                                                anchoredAt:point];
   [[menu bubble] setAlignment:info_bubble::kAlignEdgeToAnchorEdge];
   [menu showWindow:nil];
 }
 
 void BrowserWindowCocoa::ShowAvatarBubbleFromAvatarButton() {
   [[controller_ avatarButtonController] showAvatarBubble];
 }