Introduce ServiceWorkerHandle for tracking WebServiceWorkerImpl reference

content/browser/service_worker/service_worker_register_job.cc

Index: content/browser/service_worker/service_worker_register_job.cc
diff --git a/content/browser/service_worker/service_worker_register_job.cc b/content/browser/service_worker/service_worker_register_job.cc
index 21290a2f88b39821bb050b89fe87892afbea61d3..12a3a02877dcfb3686111b9a870856f06d1ebe29 100644
--- a/content/browser/service_worker/service_worker_register_job.cc
+++ b/content/browser/service_worker/service_worker_register_job.cc
@@ -101,7 +101,6 @@ void ServiceWorkerRegisterJob::HandleExistingRegistrationAndContinue(
   // registering a new one.
   // TODO(falken): Match the spec. We now throw away the active_version_ and
   // pending_version_ of the existing registration, which isn't in the spec.
-  registration->Shutdown();
   context_->storage()->DeleteRegistration(
       pattern_,
       base::Bind(&ServiceWorkerRegisterJob::RegisterAndContinue,
@@ -227,17 +226,6 @@ void ServiceWorkerRegisterJob::Complete(ServiceWorkerStatusCode status) {
   DCHECK(callbacks_.empty() || status != SERVICE_WORKER_OK);
   RunCallbacks(status, NULL);
 
-  // If |pending_version_| exists, it was not activated, so we are the sole
-  // owner of it, so it will be destroyed when this job ends, so Shutdown here.
-  // We should be able to remove this code later, when something else holds a
-  // reference to |pending_version_|.
-  // TODO(kinuko): Fix these ownership and shutdown semantics.
-  if (pending_version_) {
-    DCHECK(!registration_->pending_version());
-    DCHECK(!registration_->active_version());
-    pending_version_->Shutdown();
-  }
-
   context_->job_coordinator()->FinishJob(pattern_, this);
 }