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

chrome/browser/invalidation/fake_invalidation_service.h

Index: chrome/browser/invalidation/fake_invalidation_service.h
diff --git a/chrome/browser/invalidation/fake_invalidation_service.h b/chrome/browser/invalidation/fake_invalidation_service.h
index e990fac114940d64e7d85b40970ca8f3df575fa4..39e0fd0d3b06e930803dd083f16235a07c57ba51 100644
--- a/chrome/browser/invalidation/fake_invalidation_service.h
+++ b/chrome/browser/invalidation/fake_invalidation_service.h
@@ -33,7 +33,7 @@ class FakeInvalidationService : public InvalidationService {
 
   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;