Make use of InvalidationService

chrome/browser/invalidation/invalidation_frontend.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_INVALIDATION_INVALIDATION_FRONTEND_H_
-#define CHROME_BROWSER_INVALIDATION_INVALIDATION_FRONTEND_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:
-//
-//   frontend->RegisterInvalidationHandler(client_handler);
-//
-// When the set of IDs to register changes for the client during its lifetime
-// (i.e., between calls to RegisterInvalidationHandler(client_handler) and
-// UnregisterInvalidationHandler(client_handler):
-//
-//   frontend->UpdateRegisteredInvalidationIds(client_handler, client_ids);
-//
-// To unregister for all invalidations:
-//
-//   frontend->UnregisterInvalidationHandler(client_handler);
-//
-// If an invalidation handler cares about the invalidator state, it should also
-// do the following when starting the client:
-//
-//   invalidator_state = frontend->GetInvalidatorState();
-//
-// It can also do the above in OnInvalidatorStateChange(), or it can use the
-// argument to OnInvalidatorStateChange().
-//
-// It is an error to have registered handlers when an InvalidationFrontend is
-// shut down; clients must ensure that they unregister themselves before then.
-//
-// TODO(rlarocque): This class should extend BrowserContextKeyedService.
-//
-// NOTE(akalin): Invalidations that come in during browser shutdown may get
-// dropped.  This won't matter once we have an Acknowledge API, though: see
-// http://crbug.com/78462 and http://crbug.com/124149.
-class InvalidationFrontend {
- public:
-  // Starts sending notifications to |handler|.  |handler| must not be NULL,
-  // and it must not already be registered.
-  //
-  // Handler registrations are persisted across restarts of sync.
-  virtual void RegisterInvalidationHandler(
-      syncer::InvalidationHandler* handler) = 0;
-
-  // Updates the set of ObjectIds associated with |handler|.  |handler| must
-  // not be NULL, and must already be registered.  An ID must be registered for
-  // at most one handler.
-  //
-  // Registered IDs are persisted across restarts of sync.
-  virtual void UpdateRegisteredInvalidationIds(
-      syncer::InvalidationHandler* handler,
-      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;
-
- protected:
-  virtual ~InvalidationFrontend() { }
-};
-
-}  // namespace invalidation
-
-#endif  // CHROME_BROWSER_INVALIDATION_INVALIDATION_FRONTEND_H_