ServiceWorker: Use SimpleCache for the script cache

content/browser/service_worker/service_worker_disk_cache.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 "content/browser/service_worker/service_worker_disk_cache.h"
 
 namespace content {
 
+ServiceWorkerDiskCache::ServiceWorkerDiskCache()
+    : AppCacheDiskCache(true /* use_simple_cache */) {
+}
+
 ServiceWorkerResponseReader::ServiceWorkerResponseReader(
     int64 response_id, ServiceWorkerDiskCache* disk_cache)
     : AppCacheResponseReader(response_id, 0, disk_cache) {
 }
 
 ServiceWorkerResponseWriter::ServiceWorkerResponseWriter(
     int64 response_id, ServiceWorkerDiskCache* disk_cache)
     : AppCacheResponseWriter(response_id, 0, disk_cache) {
 }
 
 ServiceWorkerResponseMetadataWriter::ServiceWorkerResponseMetadataWriter(
     int64 response_id,
     ServiceWorkerDiskCache* disk_cache)
     : AppCacheResponseMetadataWriter(response_id, 0, disk_cache) {
 }
 
 }  // namespace content