Introduce ServiceWorkerHandle for tracking WebServiceWorkerImpl reference

content/browser/service_worker/service_worker_version_unittest.cc

 // 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.
 
 #include "base/basictypes.h"
 #include "base/run_loop.h"
 #include "content/browser/service_worker/embedded_worker_registry.h"
 #include "content/browser/service_worker/embedded_worker_test_helper.h"
 #include "content/browser/service_worker/service_worker_context_core.h"
 #include "content/browser/service_worker/service_worker_registration.h"
@@ skipping 104 matching lines @@
     version_ = new ServiceWorkerVersion(
         registration_,
         1L, context_->AsWeakPtr());
 
     // Simulate adding one process to the worker.
     int embedded_worker_id = version_->embedded_worker()->embedded_worker_id();
     helper_->SimulateAddProcessToWorker(embedded_worker_id, kRenderProcessId);
   }
 
   virtual void TearDown() OVERRIDE {
-    version_->Shutdown();
     version_ = 0;
-    registration_->Shutdown();
     registration_ = 0;
     helper_.reset();
     context_.reset();
   }
 
   TestBrowserThreadBundle thread_bundle_;
   scoped_ptr<ServiceWorkerContextCore> context_;
   scoped_ptr<EmbeddedWorkerTestHelper> helper_;
   scoped_refptr<ServiceWorkerRegistration> registration_;
   scoped_refptr<ServiceWorkerVersion> version_;
@@ skipping 185 matching lines @@
 
   // Verify that we could successfully observe repeated status changes.
   ASSERT_EQ(4U, statuses.size());
   ASSERT_EQ(ServiceWorkerVersion::INSTALLING, statuses[0]);
   ASSERT_EQ(ServiceWorkerVersion::INSTALLED, statuses[1]);
   ASSERT_EQ(ServiceWorkerVersion::ACTIVATING, statuses[2]);
   ASSERT_EQ(ServiceWorkerVersion::ACTIVE, statuses[3]);
 }
 
 }  // namespace content