Split PrefService into PrefService, PrefServiceSimple and PrefServiceSyncable.

chrome/browser/prefs/pref_value_store.h

Index: chrome/browser/prefs/pref_value_store.h
diff --git a/chrome/browser/prefs/pref_value_store.h b/chrome/browser/prefs/pref_value_store.h
index 4c027a5898196a50a8900fc218a86736306da839..47fb58e4fbcc55ad346839f510b9d28794283a4e 100644
--- a/chrome/browser/prefs/pref_value_store.h
+++ b/chrome/browser/prefs/pref_value_store.h
@@ -46,7 +46,6 @@ class PrefValueStore {
                  PrefStore* user_prefs,
                  PrefStore* recommended_prefs,
                  PrefStore* default_prefs,
-                 PrefModelAssociator* pref_sync_associator,
                  PrefNotifier* pref_notifier);
   virtual ~PrefValueStore();
 
@@ -58,9 +57,12 @@ class PrefValueStore {
                                      PrefStore* user_prefs,
                                      PrefStore* recommended_prefs,
                                      PrefStore* default_prefs,
-                                     PrefModelAssociator* pref_sync_associator,
                                      PrefNotifier* pref_notifier);
 
+  // TODO(joi): Remove this completely; the part PrefModelAssociator
+  // needs can be handled simply as a PrefObserver.
+  void set_sync_associator(PrefModelAssociator* sync_associator);
+
   // Gets the value for the given preference name that has the specified value
   // type. Values stored in a PrefStore that have the matching |name| but
   // a non-matching |type| are silently skipped. Returns true if a valid value