[Sync] Avoid unregistering object IDs on shutdown

chrome/browser/sync/profile_sync_service.h

Index: chrome/browser/sync/profile_sync_service.h
diff --git a/chrome/browser/sync/profile_sync_service.h b/chrome/browser/sync/profile_sync_service.h
index 3dee74f3a9686fad5632d1a997bac35a9899d7d0..b0013ef5a895696787279bb5ce34186e41a11c82 100644
--- a/chrome/browser/sync/profile_sync_service.h
+++ b/chrome/browser/sync/profile_sync_service.h
@@ -551,14 +551,23 @@ class ProfileSyncService : public browser_sync::SyncFrontend,
   // been cleared yet. Virtual for testing purposes.
   virtual bool waiting_for_auth() const;
 
-  // Updates the set of ObjectIds associated with a given
-  // |handler|. Passing an empty ObjectIdSet will unregister
-  // |handler|. There should be at most one handler registered per
-  // object id.
+  // Sets the invalidation handler for the given name.  Pass in NULL
+  // for |handler| if you want to remove the handler for the given
+  // name.  (This doesn't unregister the IDs for the given name,
+  // though.)  A handler must be set for at most one name.
   //
-  // The handler -> registered ids map is persisted across restarts of
+  // The handler name -> handler map is persisted across restarts of
   // sync.
-  void UpdateRegisteredInvalidationIds(syncer::SyncNotifierObserver* handler,
+  void SetInvalidationHandler(const std::string& handler_name,
+                              syncer::SyncNotifierObserver* handler);
+
+  // Updates the set of ObjectIds associated with a given invalidation
+  // handler (via its name). An ID must be registered for at most one
+  // handler.
+  //
+  // The handler name -> registered ids map is persisted across
+  // restarts of sync.
+  void UpdateRegisteredInvalidationIds(const std::string& handler_name,
                                        const syncer::ObjectIdSet& ids);
 
   // ProfileKeyedService implementation.
@@ -835,9 +844,6 @@ class ProfileSyncService : public browser_sync::SyncFrontend,
   // Factory the backend will use to build the SyncManager.
   syncer::SyncManagerFactory sync_manager_factory_;
 
-  // The set of all registered IDs.
-  syncer::ObjectIdSet all_registered_ids_;
-
   // Dispatches invalidations to handlers.
   syncer::SyncNotifierHelper notifier_helper_;