[Sync] InvalidationService shouldn't CHECK when registering ObjectId for more than one handler

chrome/browser/sync/test/integration/fake_server_invalidation_service.h

 // Copyright 2014 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_TEST_INTEGRATION_FAKE_SERVER_INVALIDATION_SERVICE_H_
 #define CHROME_BROWSER_SYNC_TEST_INTEGRATION_FAKE_SERVER_INVALIDATION_SERVICE_H_
 
 #include <string>
 #include <utility>
 
@@ skipping 13 matching lines @@
 
 // An InvalidationService that is used in conjunction with FakeServer.
 class FakeServerInvalidationService : public invalidation::InvalidationService,
                                       public FakeServer::Observer {
  public:
   FakeServerInvalidationService();
   ~FakeServerInvalidationService() override;
 
   void RegisterInvalidationHandler(
       syncer::InvalidationHandler* handler) override;
-  void UpdateRegisteredInvalidationIds(syncer::InvalidationHandler* handler,
+  bool UpdateRegisteredInvalidationIds(syncer::InvalidationHandler* handler,
                                        const syncer::ObjectIdSet& ids) override;
   void UnregisterInvalidationHandler(
       syncer::InvalidationHandler* handler) override;
 
   syncer::InvalidatorState GetInvalidatorState() const override;
   std::string GetInvalidatorClientId() const override;
   invalidation::InvalidationLogger* GetInvalidationLogger() override;
   void RequestDetailedStatus(
       base::Callback<void(const base::DictionaryValue&)> caller) const override;
   IdentityProvider* GetIdentityProvider() override;
@@ skipping 14 matching lines @@
   syncer::InvalidatorRegistrar invalidator_registrar_;
   FakeProfileOAuth2TokenService token_service_;
   FakeIdentityProvider identity_provider_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeServerInvalidationService);
 };
 
 }  // namespace fake_server
 
 #endif  // CHROME_BROWSER_SYNC_TEST_INTEGRATION_FAKE_SERVER_INVALIDATION_SERVICE_H_