Introduce PrefRegistrySyncable, simplifying PrefServiceSyncable.

chrome/test/base/testing_profile.h

 // 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.
 
 #ifndef CHROME_TEST_BASE_TESTING_PROFILE_H_
 #define CHROME_TEST_BASE_TESTING_PROFILE_H_
 
 #include <string>
 
 #include "base/files/scoped_temp_dir.h"
@@ skipping 219 matching lines @@
   net::CookieMonster* GetCookieMonster();
 
   virtual policy::ManagedModePolicyProvider*
       GetManagedModePolicyProvider() OVERRIDE;
   virtual policy::PolicyService* GetPolicyService() OVERRIDE;
   // Sets the profile's PrefService. If a pref service hasn't been explicitly
   // set GetPrefs creates one, so normally you need not invoke this. If you need
   // to set a pref service you must invoke this before GetPrefs.
   // TestingPrefService takes ownership of |prefs|.
   void SetPrefService(PrefServiceSyncable* prefs);
-  virtual PrefServiceSyncable* GetPrefs() OVERRIDE;
+  virtual PrefService* GetPrefs() OVERRIDE;
   virtual history::TopSites* GetTopSites() OVERRIDE;
   virtual history::TopSites* GetTopSitesWithoutCreating() OVERRIDE;
 
   void CreateRequestContext();
   // Clears out the created request context (which must be done before shutting
   // down the IO thread to avoid leaks).
   void ResetRequestContext();
 
   virtual net::URLRequestContextGetter* GetMediaRequestContext() OVERRIDE;
   virtual net::URLRequestContextGetter* GetMediaRequestContextForRenderProcess(
@@ skipping 57 matching lines @@
   // task is processed.  This has the effect of blocking the caller until the
   // history service processes all pending requests.
   void BlockUntilHistoryProcessesPendingRequests();
 
   virtual chrome_browser_net::Predictor* GetNetworkPredictor() OVERRIDE;
   virtual void ClearNetworkingHistorySince(
       base::Time time,
       const base::Closure& completion) OVERRIDE;
   virtual GURL GetHomePage() OVERRIDE;
 
-  virtual PrefServiceSyncable* GetOffTheRecordPrefs() OVERRIDE;
+  virtual PrefService* GetOffTheRecordPrefs() OVERRIDE;
 
  protected:
   base::Time start_time_;
   scoped_ptr<PrefServiceSyncable> prefs_;
   // ref only for right type, lifecycle is managed by prefs_
   TestingPrefServiceSyncable* testing_prefs_;
 
  private:
   // Creates a temporary directory for use by this profile.
   void CreateTempProfileDir();
@@ skipping 47 matching lines @@
   // testing.
   ProfileDependencyManager* profile_dependency_manager_;
 
   scoped_ptr<content::MockResourceContext> resource_context_;
 
   // Weak pointer to a delegate for indicating that a profile was created.
   Delegate* delegate_;
 };
 
 #endif  // CHROME_TEST_BASE_TESTING_PROFILE_H_