Implement new invalidations ack tracking system

chrome/browser/invalidation/invalidation_service.h

 // Copyright 2013 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_INVALIDATION_INVALIDATION_SERVICE_H_
 #define CHROME_BROWSER_INVALIDATION_INVALIDATION_SERVICE_H_
 
 #include "components/browser_context_keyed_service/browser_context_keyed_service.h"
 #include "sync/notifier/invalidation_util.h"
 #include "sync/notifier/invalidator_state.h"
 
 namespace syncer {
 class InvalidationHandler;
-class AckHandle;
 }  // namespace syncer
 
 namespace invalidation {
 
 // Interface for classes that handle invalidation registrations and send out
 // invalidations to register handlers.
 //
 // Invalidation clients should follow the pattern below:
 //
 // When starting the client:
@@ skipping 59 matching lines @@
       const syncer::ObjectIdSet& ids) = 0;
 
   // Stops sending notifications to |handler|.  |handler| must not be NULL, and
   // it must already be registered.  Note that this doesn't unregister the IDs
   // associated with |handler|.
   //
   // Handler registrations are persisted across restarts of sync.
   virtual void UnregisterInvalidationHandler(
       syncer::InvalidationHandler* handler) = 0;
 
-  // Sends an acknowledgement that an invalidation for |id| was successfully
-  // handled.
-  virtual void AcknowledgeInvalidation(const invalidation::ObjectId& id,
-                                       const syncer::AckHandle& ack_handle) = 0;
-
   // Returns the current invalidator state.  When called from within
   // InvalidationHandler::OnInvalidatorStateChange(), this must return
   // the updated state.
   virtual syncer::InvalidatorState GetInvalidatorState() const = 0;
 
   // Returns the ID belonging to this invalidation client.  Can be used to
   // prevent the receipt of notifications of our own changes.
   virtual std::string GetInvalidatorClientId() const = 0;
 
  protected:
   virtual ~InvalidationService() { }
 };
 
 }  // namespace invalidation
 
 #endif  // CHROME_BROWSER_INVALIDATION_INVALIDATION_SERVICE_H_