ServiceWorker: Introduce SWMessageSender in order to mock IPC messaging

content/child/service_worker/service_worker_message_sender.h

Index: content/child/service_worker/service_worker_message_sender.h
diff --git a/content/child/service_worker/service_worker_message_sender.h b/content/child/service_worker/service_worker_message_sender.h
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index 0000000000000000000000000000000000000000..e1732f2ea8c7cae22021f4451138a97ab2384f1f
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+++ b/content/child/service_worker/service_worker_message_sender.h
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+// 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_CHILD_SERVICE_WORKER_SERVICE_WORKER_MESSAGE_SENDER_H_
+#define CONTENT_CHILD_SERVICE_WORKER_SERVICE_WORKER_MESSAGE_SENDER_H_
+
+#include "base/memory/ref_counted.h"
+#include "content/common/content_export.h"
+
+namespace IPC {
+class Message;
+}
+
+namespace content {
+
+class ThreadSafeSender;
+
+// A thin wrapper of ThreadSafeSender. Tests can inject a mock for IPC messaging
+// in this layer.
+class CONTENT_EXPORT ServiceWorkerMessageSender
+    : public base::RefCountedThreadSafe<ServiceWorkerMessageSender> {
+ public:
+  explicit ServiceWorkerMessageSender(ThreadSafeSender* sender);
+
+  virtual bool Send(IPC::Message* message);
+
+  ThreadSafeSender* thread_safe_sender() { return thread_safe_sender_.get(); }
+
+ protected:
+  virtual ~ServiceWorkerMessageSender();
+
+ private:
+  friend class base::RefCountedThreadSafe<ServiceWorkerMessageSender>;
+
+  scoped_refptr<ThreadSafeSender> thread_safe_sender_;
+
+  DISALLOW_COPY_AND_ASSIGN(ServiceWorkerMessageSender);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_CHILD_SERVICE_WORKER_SERVICE_WORKER_MESSAGE_SENDER_H_