ServiceWorker: Migrate the script cache backend from BlockFile to Simple

content/browser/service_worker/service_worker_disk_cache_migrator.h

Index: content/browser/service_worker/service_worker_disk_cache_migrator.h
diff --git a/content/browser/service_worker/service_worker_disk_cache_migrator.h b/content/browser/service_worker/service_worker_disk_cache_migrator.h
index 283db71a4abfde10662b44ed6874650eb704b2b3..4f777be35b501153f57c8af67711c797cb545ada 100644
--- a/content/browser/service_worker/service_worker_disk_cache_migrator.h
+++ b/content/browser/service_worker/service_worker_disk_cache_migrator.h
@@ -31,7 +31,9 @@ class CONTENT_EXPORT ServiceWorkerDiskCacheMigrator {
   void Start(const StatusCallback& callback);
 
  private:
-  friend class ServiceWorkerDiskCacheMigratorTest;
+  FRIEND_TEST_ALL_PREFIXES(ServiceWorkerDiskCacheMigratorTest,
+                           ThrottleInflightTasks);
+
   class Task;
   class WrappedEntry;
 
@@ -59,6 +61,9 @@ class CONTENT_EXPORT ServiceWorkerDiskCacheMigrator {
   scoped_ptr<Task> pending_task_;
   size_t max_number_of_inflight_tasks_ = 10;
 
+  base::TimeTicks start_time_;
+  size_t number_of_migrated_resources_ = 0;
+
   StatusCallback callback_;
 
   base::WeakPtrFactory<ServiceWorkerDiskCacheMigrator> weak_factory_;