Decouple Cache Storage messaging from Service Worker/Embedded Worker

content/browser/service_worker/cache_storage_dispatcher_host.h

Index: content/browser/service_worker/cache_storage_dispatcher_host.h
diff --git a/content/browser/service_worker/cache_storage_dispatcher_host.h b/content/browser/service_worker/cache_storage_dispatcher_host.h
new file mode 100644
index 0000000000000000000000000000000000000000..0c674a760e61d3776ff749dddde8e951c8d0d93e
--- /dev/null
+++ b/content/browser/service_worker/cache_storage_dispatcher_host.h
@@ -0,0 +1,50 @@
+// Copyright 2015 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_CACHE_STORAGE_DISPATCHER_HOST_H_
+#define CONTENT_BROWSER_SERVICE_WORKER_CACHE_STORAGE_DISPATCHER_HOST_H_
+
+#include "content/public/browser/browser_message_filter.h"
+
+namespace content {
+
+class CacheStorageContextImpl;
+class ServiceWorkerCacheListener;
+
+// Handles Cache Storage related messages sent to the browser process from
+// child processes. One host instance exists per child process. All
+// messages are processed on the IO thread. Currently, all messages are
+// passed directly to the owned ServiceWorkerCacheListener instance, which
+// in turn dispatches calls to the ServiceWorkerCacheStorageManager owned
+// by the CacheStorageContextImpl for the entire browsing context.
+// TODO(jsbell): Merge this with ServiceWorkerCacheListener crbug.com/439389
+class CONTENT_EXPORT CacheStorageDispatcherHost : public BrowserMessageFilter {
+ public:
+  CacheStorageDispatcherHost();
+
+  // Runs on UI thread.
+  void Init(CacheStorageContextImpl* context);
+
+  // BrowserMessageFilter implementation
+  void OnDestruct() const override;
+  bool OnMessageReceived(const IPC::Message& message) override;
+
+ private:
+  // Friends to allow OnDestruct() delegation
+  friend class BrowserThread;
+  friend class base::DeleteHelper<CacheStorageDispatcherHost>;
+
+  ~CacheStorageDispatcherHost() override;
+
+  // Called by Init() on IO thread.
+  void CreateCacheListener(CacheStorageContextImpl* context);
+
+  scoped_ptr<ServiceWorkerCacheListener> cache_listener_;
+
+  DISALLOW_COPY_AND_ASSIGN(CacheStorageDispatcherHost);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_SERVICE_WORKER_CACHE_STORAGE_DISPATCHER_HOST_H_