Remove the last usages of PrefObserver outside of Prefs.

chrome/browser/ui/sync/one_click_signin_helper_unittest.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 "base/command_line.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/content_settings/cookie_settings.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/prefs/scoped_user_pref_update.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 45 matching lines @@
 };
 
 class TestProfileIOData : public ProfileIOData {
  public:
   TestProfileIOData(bool is_incognito, PrefService* pref_service,
                     PrefService* local_state, CookieSettings* cookie_settings)
       : ProfileIOData(is_incognito) {
     // Initialize the IO members required for these tests, but keep them on
     // this thread since we don't use a background thread here.
     google_services_username()->Init(prefs::kGoogleServicesUsername,
-                                     pref_service, NULL);
+                                     pref_service);
     reverse_autologin_enabled()->Init(prefs::kReverseAutologinEnabled,
-                                      pref_service, NULL);
+                                      pref_service);
     one_click_signin_rejected_email_list()->Init(
-        prefs::kReverseAutologinRejectedEmailList, pref_service, NULL);
+        prefs::kReverseAutologinRejectedEmailList, pref_service);
 
     google_services_username_pattern()->Init(
-        prefs::kGoogleServicesUsernamePattern, local_state, NULL);
+        prefs::kGoogleServicesUsernamePattern, local_state);
 
     set_signin_names_for_testing(new SigninNamesOnIOThread());
     SetCookieSettingsForTesting(cookie_settings);
   }
 
   virtual ~TestProfileIOData() {
     signin_names()->ReleaseResourcesOnUIThread();
   }
 
   // ProfileIOData overrides:
@@ skipping 471 matching lines @@
                 valid_gaia_url_, "", &request_, io_data.get()));
 }
 
 TEST_F(OneClickSigninHelperIOTest, CanOfferOnIOThreadNoSigninCookies) {
   AllowSigninCookies(false);
   scoped_ptr<TestProfileIOData> io_data(CreateTestProfileIOData(false));
   EXPECT_EQ(OneClickSigninHelper::DONT_OFFER,
             OneClickSigninHelper::CanOfferOnIOThreadImpl(
                 valid_gaia_url_, "", &request_, io_data.get()));
 }