Remove the last usages of PrefObserver outside of Prefs.

chrome/browser/tab_contents/spelling_menu_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/tab_contents/spelling_menu_observer.h"
 
 #include "base/bind.h"
 #include "base/i18n/case_conversion.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/app/chrome_command_ids.h"
@@ skipping 18 matching lines @@
 #include "ui/gfx/rect.h"
 
 using content::BrowserThread;
 
 SpellingMenuObserver::SpellingMenuObserver(RenderViewContextMenuProxy* proxy)
     : proxy_(proxy),
       loading_frame_(0),
       succeeded_(false) {
   if (proxy && proxy->GetProfile())
     integrate_spelling_service_.Init(prefs::kSpellCheckUseSpellingService,
-                                     proxy->GetProfile()->GetPrefs(), NULL);
+                                     proxy->GetProfile()->GetPrefs());
 }
 
 SpellingMenuObserver::~SpellingMenuObserver() {
 }
 
 void SpellingMenuObserver::InitMenu(const content::ContextMenuParams& params) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!params.misspelled_word.empty() ||
       params.dictionary_suggestions.empty());
 
@@ skipping 244 matching lines @@
 void SpellingMenuObserver::OnAnimationTimerExpired() {
   // Append '.' characters to the end of "Checking".
   loading_frame_ = (loading_frame_ + 1) & 3;
   string16 loading_message = loading_message_ + string16(loading_frame_,'.');
 
   // Update the menu item with the text. We disable this item to prevent users
   // from selecting it.
   proxy_->UpdateMenuItem(IDC_CONTENT_CONTEXT_SPELLING_SUGGESTION, false, false,
                          loading_message);
 }