Implement WebPushProvider.unregister() in Chromium.

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 "content/public/common/push_messaging_status.h"
 #include "third_party/WebKit/public/platform/WebPushPermissionStatus.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. Must only be used on the UI thread.
 class CONTENT_EXPORT PushMessagingService {
  public:
-  typedef base::Callback<void(const std::string& /* registration_id */,
-                              PushRegistrationStatus /* status */)>
-      RegisterCallback;
+  using RegisterCallback =
+      base::Callback<void(const std::string& /* registration_id */,
+                          PushRegistrationStatus /* status */)>;
+  using UnregisterCallback = base::Callback<void(bool)>;
 
   virtual ~PushMessagingService() {}
 
   // Returns the absolute URL exposed by the push server where the webapp server
   // can send push messages. This is currently assumed to be the same for all
   // origins and push registrations.
   virtual GURL GetPushEndpoint() = 0;
 
   // Register the given |sender_id| with the push messaging service in a
   // document context. The frame is known and a permission UI may be displayed
@@ skipping 22 matching lines @@
       const GURL& requesting_origin,
       int renderer_id,
       int render_frame_id) = 0;
 
   // Checks the permission status for the requesting origin. Permission is only
   // ever granted when the requesting origin matches the top level embedding
   // origin.
   virtual blink::WebPushPermissionStatus GetPermissionStatus(
       const GURL& requesting_origin,
       const GURL& embedding_origin) = 0;
+
+  // Unregister an origin and its associated service worker registration id from
+  // the push service.
+  virtual void Unregister(const GURL& requesting_origin,
+                          int64 service_worker_registration_id,
+                          const UnregisterCallback& callback) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_PUSH_MESSAGING_SERVICE_H_