Remove PrefServiceSimple, replacing it with PrefService and PrefRegistrySimple.

chrome/browser/prefs/pref_service_syncable.h

Index: chrome/browser/prefs/pref_service_syncable.h
diff --git a/chrome/browser/prefs/pref_service_syncable.h b/chrome/browser/prefs/pref_service_syncable.h
index c0da1356977e11ef2dfebdcab2397e0ebe92f6f2..af2b8587b2fa861158fb9afb089723b1ae238436 100644
--- a/chrome/browser/prefs/pref_service_syncable.h
+++ b/chrome/browser/prefs/pref_service_syncable.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_PREFS_PREF_SERVICE_SYNCABLE_H_
 
 #include "chrome/browser/prefs/pref_model_associator.h"
+#include "chrome/browser/prefs/pref_registry.h"
 #include "chrome/browser/prefs/pref_service.h"
 
 class PrefServiceSyncableObserver;
@@ -33,7 +34,7 @@ class PrefServiceSyncable : public PrefService {
       PrefNotifierImpl* pref_notifier,
       PrefValueStore* pref_value_store,
       PersistentPrefStore* user_prefs,
-      DefaultPrefStore* default_store,
+      scoped_ptr<PrefRegistry> pref_registry,
       base::Callback<void(PersistentPrefStore::PrefReadError)>
           read_error_callback,
       bool async);
@@ -55,8 +56,6 @@ class PrefServiceSyncable : public PrefService {
   void AddObserver(PrefServiceSyncableObserver* observer);
   void RemoveObserver(PrefServiceSyncableObserver* observer);
 
-  virtual void UnregisterPreference(const char* path) OVERRIDE;
-
   void RegisterBooleanPref(const char* path,
                            bool default_value,
                            PrefSyncStatus sync_status);
@@ -101,6 +100,8 @@ class PrefServiceSyncable : public PrefService {
                           uint64 default_value,
                           PrefSyncStatus sync_status);
 
+  void UnregisterPreference(const char* path);
+
   // TODO(zea): Have PrefServiceSyncable implement
   // syncer::SyncableService directly.
   syncer::SyncableService* GetSyncableService();
@@ -111,6 +112,11 @@ class PrefServiceSyncable : public PrefService {
  private:
   friend class PrefModelAssociator;
 
+  // TODO(joi): Temporary; to be replaced with PrefRegistrarSyncable.
+  friend class PrefsTabHelper;
+
+  virtual bool AllowPrefRegistrarSimple() const OVERRIDE;
+
   // Invoked internally when the IsSyncing() state changes.
   void OnIsSyncingChanged();