Revert r276792 - "Hook PushMessagingMessageFilter up to GCMDriver"

content/public/browser/push_messaging_service.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_PUBLIC_BROWSER_PUSH_MESSAGING_SERVICE_H_
-#define CONTENT_PUBLIC_BROWSER_PUSH_MESSAGING_SERVICE_H_
-
-#include <string>
-
-#include "base/callback.h"
-#include "content/common/content_export.h"
-#include "url/gurl.h"
-
-namespace content {
-
-// A push service-agnostic interface that the Push API uses for talking to
-// push messaging services like GCM.
-class CONTENT_EXPORT PushMessagingService {
- public:
-  typedef base::Callback<void(const GURL& /* endpoint */,
-                              const std::string& /* registration_id */,
-                              bool /* error */)>
-      RegisterCallback;
-
-  virtual ~PushMessagingService() {}
-  virtual void Register(const std::string& app_id,
-                        const std::string& sender_id,
-                        const RegisterCallback& callback) = 0;
-};
-
-}  // namespace content
-
-#endif  // CONTENT_PUBLIC_BROWSER_PUSH_MESSAGING_SERVICE_H_