sync: migrate invalidation state from syncable::Directory to InvalidationStorage

sync/notifier/invalidation_notifier.h

Index: sync/notifier/invalidation_notifier.h
diff --git a/sync/notifier/invalidation_notifier.h b/sync/notifier/invalidation_notifier.h
index a287a6f90f2831d57aa230f295baf3c2b7324a6b..db162986acaa3982c4f73f02a8bf96b12b8766f0 100644
--- a/sync/notifier/invalidation_notifier.h
+++ b/sync/notifier/invalidation_notifier.h
@@ -35,13 +35,13 @@ namespace sync_notifier {
 class InvalidationNotifier
     : public SyncNotifier,
       public notifier::LoginDelegate,
-      public ChromeInvalidationClient::Listener,
-      public StateWriter {
+      public ChromeInvalidationClient::Listener {
  public:
   // |invalidation_state_tracker| must be initialized.
   InvalidationNotifier(
       const notifier::NotifierOptions& notifier_options,
       const InvalidationVersionMap& initial_max_invalidation_versions,
+      const std::string& initial_invalidation_state,
       const browser_sync::WeakHandle<InvalidationStateTracker>&
           invalidation_state_tracker,
       const std::string& client_info);
@@ -52,7 +52,7 @@ class InvalidationNotifier
   virtual void AddObserver(SyncNotifierObserver* observer) OVERRIDE;
   virtual void RemoveObserver(SyncNotifierObserver* observer) OVERRIDE;
   virtual void SetUniqueId(const std::string& unique_id) OVERRIDE;
-  virtual void SetState(const std::string& state) OVERRIDE;
+  virtual void SetStateDeprecated(const std::string& state) OVERRIDE;
   virtual void UpdateCredentials(
       const std::string& email, const std::string& token) OVERRIDE;
   virtual void UpdateEnabledTypes(
@@ -70,9 +70,6 @@ class InvalidationNotifier
       const syncable::ModelTypePayloadMap& type_payloads) OVERRIDE;
   virtual void OnSessionStatusChanged(bool has_session) OVERRIDE;
 
-  // StateWriter implementation.
-  virtual void WriteState(const std::string& state) OVERRIDE;
-
  private:
   base::NonThreadSafe non_thread_safe_;
 
@@ -107,6 +104,8 @@ class InvalidationNotifier
   std::string invalidation_client_id_;
 
   // The state to pass to |chrome_invalidation_client_|.
+  // TODO(tim): This should be made const once migration is completed for bug
+  // 124140.
   std::string invalidation_state_;
 
   // The XMPP connection manager.