Split PrefService into PrefService, PrefServiceSimple and PrefServiceSyncable.

chrome/browser/net/pref_proxy_config_tracker_impl.h

Index: chrome/browser/net/pref_proxy_config_tracker_impl.h
diff --git a/chrome/browser/net/pref_proxy_config_tracker_impl.h b/chrome/browser/net/pref_proxy_config_tracker_impl.h
index 9157f55c3a9e0de825a6e7c845df751dcffe6015..2e56bf8a1b039b1732471bef88439f7c865c02d1 100644
--- a/chrome/browser/net/pref_proxy_config_tracker_impl.h
+++ b/chrome/browser/net/pref_proxy_config_tracker_impl.h
@@ -15,6 +15,7 @@
 #include "net/proxy/proxy_config_service.h"
 
 class PrefService;
+class PrefServiceSyncable;
 
 // A net::ProxyConfigService implementation that applies preference proxy
 // settings (pushed from PrefProxyConfigTrackerImpl) as overrides to the proxy
@@ -117,7 +118,7 @@ class PrefProxyConfigTrackerImpl {
                                     net::ProxyConfig* config);
 
   // Registers the proxy preference.
-  static void RegisterPrefs(PrefService* user_prefs);
+  static void RegisterPrefs(PrefServiceSyncable* user_prefs);
 
  protected:
   // Get the proxy configuration currently defined by preferences.