[ServiceWorkerCache] Return the real size of the cache in GetOriginUsage.

content/browser/service_worker/service_worker_cache.h

 // 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.
 
 #ifndef CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_CACHE_H_
 #define CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_CACHE_H_
 
 #include "base/callback.h"
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
@@ skipping 72 matching lines @@
               const ErrorCallback& callback);
 
   // TODO(jkarlin): Have keys take an optional ServiceWorkerFetchRequest.
   // Returns ErrorTypeOK and a vector of requests if there are no errors. The
   // callback will always be called.
   void Keys(const RequestsCallback& callback);
 
   // Prevent further operations on this object and delete the backend.
   void Close();
 
+  // The size of the cache contents in memory. Returns 0 if the cache backend is
+  // not a memory cache backend.
+  int64 MemoryBackedSize() const;
+
   void set_backend(scoped_ptr<disk_cache::Backend> backend) {
     backend_ = backend.Pass();
   }
 
   base::WeakPtr<ServiceWorkerCache> AsWeakPtr();
 
  private:
   friend class base::RefCounted<ServiceWorkerCache>;
 
   struct KeysContext;
@@ skipping 36 matching lines @@
   // check for its existence before use.
   scoped_ptr<disk_cache::Backend> backend_;
   GURL origin_;
   base::FilePath path_;
   net::URLRequestContext* request_context_;
   scoped_refptr<storage::QuotaManagerProxy> quota_manager_proxy_;
   base::WeakPtr<storage::BlobStorageContext> blob_storage_context_;
   bool initialized_;
   std::vector<base::Closure> init_callbacks_;
 
+  // Whether or not to store data in disk or memory.
+  bool memory_only_;
+
   base::WeakPtrFactory<ServiceWorkerCache> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceWorkerCache);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_CACHE_H_