Make //content responsible for generating notification Ids

chrome/browser/notifications/stub_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_STUB_NOTIFICATION_PLATFORM_BRIDGE_H_
 #define CHROME_BROWSER_NOTIFICATIONS_STUB_NOTIFICATION_PLATFORM_BRIDGE_H_
 
 #include <unordered_map>
 #include <vector>
 
@@ skipping 15 matching lines @@
   void Display(NotificationCommon::Type notification_type,
                const std::string& notification_id,
                const std::string& profile_id,
                bool incognito,
                const Notification& notification) override;
   void Close(const std::string& profile_id,
              const std::string& notification_id) override;
   bool GetDisplayed(const std::string& profile_id,
                     bool incognito,
                     std::set<std::string>* notifications) const override;
-  bool SupportsNotificationCenter() const override;
 
  private:
   // Map of profile Ids to list of notifications shown for said profile.
   std::unordered_map<std::string, std::vector<Notification>> notifications_;
 
   DISALLOW_COPY_AND_ASSIGN(StubNotificationPlatformBridge);
 };
 
 #endif  // CHROME_BROWSER_NOTIFICATIONS_STUB_NOTIFICATION_PLATFORM_BRIDGE_H_