Refactor NotificationPlatformBridgeLinux

chrome/browser/notifications/notification_platform_bridge.h

 // Copyright 2016 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 CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_PLATFORM_BRIDGE_H_
 #define CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_PLATFORM_BRIDGE_H_
 
 #include <memory>
 #include <set>
 #include <string>
 
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "chrome/browser/notifications/displayed_notifications_dispatch_callback.h"
 #include "chrome/browser/notifications/notification_common.h"
 
 class Notification;
 
 // Provides the low-level interface that enables notifications to be displayed
 // and interacted with on the user's screen, orthogonal of whether this
 // functionality is provided by the browser or by the operating system.
 // TODO(miguelg): Add support for click and close events.
 class NotificationPlatformBridge {
  public:
+  using NotificationBridgeReadyCallback =
+      base::OnceCallback<void(bool /* success */)>;
+
   static NotificationPlatformBridge* Create();
 
   virtual ~NotificationPlatformBridge() {}
 
   // Shows a toast on screen using the data passed in |notification|.
   virtual void Display(NotificationCommon::Type notification_type,
                        const std::string& notification_id,
                        const std::string& profile_id,
                        bool is_incognito,
                        const Notification& notification) = 0;
 
   // Closes a nofication with |notification_id| and |profile_id| if being
   // displayed.
   virtual void Close(const std::string& profile_id,
                      const std::string& notification_id) = 0;
 
   // Writes the ids of all currently displaying notifications and posts
   // |callback| with the result.
   virtual void GetDisplayed(
       const std::string& profile_id,
       bool incognito,
       const GetDisplayedNotificationsCallback& callback) const = 0;
 
+  // Calls |callback| once |this| is initialized. The argument is
+  // true if |this| is ready to be used and false if initialization
+  // failed. |callback| may be called directly or from a posted task.
+  virtual void SetReadyCallback(NotificationBridgeReadyCallback callback) = 0;
+
  protected:
   NotificationPlatformBridge() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(NotificationPlatformBridge);
 };
 
 #endif  // CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_PLATFORM_BRIDGE_H_