Split PrefService into PrefService, PrefServiceSimple and PrefServiceSyncable.

chrome/browser/ui/window_snapshot/window_snapshot.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/ui/window_snapshot/window_snapshot.h"
 
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/common/pref_names.h"
 
 namespace chrome {
 
 bool GrabWindowSnapshotForUser(
     gfx::NativeWindow window,
     std::vector<unsigned char>* png_representation,
     const gfx::Rect& snapshot_bounds) {
   if (g_browser_process->local_state()->GetBoolean(prefs::kDisableScreenshots))
     return false;
   return internal::GrabWindowSnapshot(window, png_representation,
         snapshot_bounds);
 }
 
-void RegisterScreenshotPrefs(PrefService* service) {
+void RegisterScreenshotPrefs(PrefServiceSimple* service) {
   service->RegisterBooleanPref(prefs::kDisableScreenshots, false);
 }
 
 }  // namespace browser