Plumb invalidations from Tango to the extensions code for the Push Messaging API.

chrome/browser/sync/invalidation_service.h

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_SYNC_INVALIDATION_SERVICE_H_
+#define CHROME_BROWSER_SYNC_INVALIDATION_SERVICE_H_
+
+#include "sync/notifier/invalidation_util.h"
+
+namespace syncer {
+class SyncNotifierObserver;
+}  // namespace syncer
+
+// TODO(dcheng): Add an interesting comment here.
+class InvalidationService {
+ public:
+  virtual ~InvalidationService() { }
+
+  // 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.
+  virtual void UpdateRegisteredInvalidationIds(
+      syncer::SyncNotifierObserver* handler,
+      const syncer::ObjectIdSet& ids) = 0;
+};
+
+#endif  // CHROME_BROWSER_SYNC_INVALIDATION_SERVICE_H_