Introduce PrefRegistrySyncable, simplifying PrefServiceSyncable.

chrome/browser/signin/signin_manager_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 "chrome/browser/signin/signin_manager.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/compiler_specific.h"
 #include "base/stringprintf.h"
@@ skipping 47 matching lines @@
     // thread, if it does not already exist. But it must be created on the IO
     // thread or else it will DCHECK upon destruction.
     // Force it to be created here.
     profile_->CreateRequestContext();
     profile_->GetRequestContext()->GetURLRequestContext();
     io_setup_complete->Signal();
   }
 
   virtual void SetUp() OVERRIDE {
     prefs_.reset(new TestingPrefServiceSimple);
-    chrome::RegisterLocalState(prefs_->registry(), prefs_.get());
+    chrome::RegisterLocalState(prefs_.get(), prefs_->registry());
     TestingBrowserProcess::GetGlobal()->SetLocalState(
         prefs_.get());
     TokenServiceTestHarness::SetUp();
     manager_.reset(new SigninManager());
     google_login_success_.ListenFor(
         chrome::NOTIFICATION_GOOGLE_SIGNIN_SUCCESSFUL,
         content::Source<Profile>(profile_.get()));
     google_login_failure_.ListenFor(chrome::NOTIFICATION_GOOGLE_SIGNIN_FAILED,
                                     content::Source<Profile>(profile_.get()));
 
@@ skipping 568 matching lines @@
 
   manager_->ProvideOAuthChallengeResponse(
       GoogleServiceAuthError::CAPTCHA_REQUIRED, "token", "solution");
 
   SimulateProvideOAuthChallengeResponseValid();
   EXPECT_EQ("user@gmail.com", manager_->GetAuthenticatedUsername());
 
   EXPECT_EQ(1U, google_login_success_.size());
   EXPECT_EQ(1U, google_login_failure_.size());
 }