Implement PermissionService::GetNextPermissionChange.

content/shell/browser/shell_permission_manager.h

 // 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_SHELL_BROWSER_SHELL_PERMISSION_MANAGER_H_
 #define CONTENT_SHELL_BROWSER_SHELL_PERMISSION_MANAGER_H_
 
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "content/public/browser/permission_manager.h"
@@ skipping 19 matching lines @@
                                const GURL& requesting_origin) override;
   void ResetPermission(PermissionType permission,
                        const GURL& requesting_origin,
                        const GURL& embedding_origin) override;
   PermissionStatus GetPermissionStatus(PermissionType permission,
                                        const GURL& requesting_origin,
                                        const GURL& embedding_origin) override;
   void RegisterPermissionUsage(PermissionType permission,
                                const GURL& requesting_origin,
                                const GURL& embedding_origin) override;
+  int SubscribePermissionStatusChange(
+      PermissionType permission,
+      const GURL& requesting_origin,
+      const GURL& embedding_origin,
+      const base::Callback<void(PermissionStatus)>& callback) override;
+  void UnsubscribePermissionStatusChange(int subscription_id) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ShellPermissionManager);
 };
 
 }  // namespace content
 
 #endif // CONTENT_SHELL_BROWSER_SHELL_PERMISSION_MANAGER_H