[Extensions] Make Event::restrict_to_browser_context const.

chrome/browser/extensions/api/signed_in_devices/signed_in_devices_manager.cc

 // Copyright 2013 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.
 
 #include "chrome/browser/extensions/api/signed_in_devices/signed_in_devices_manager.h"
 
 #include <memory>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 57 matching lines @@
 
   std::vector<api::signed_in_devices::DeviceInfo> args;
   for (const std::unique_ptr<DeviceInfo>& info : devices) {
     api::signed_in_devices::DeviceInfo api_device;
     FillDeviceInfo(*info, &api_device);
     args.push_back(std::move(api_device));
   }
 
   std::unique_ptr<base::ListValue> result =
       api::signed_in_devices::OnDeviceInfoChange::Create(args);
-  std::unique_ptr<Event> event(
-      new Event(events::SIGNED_IN_DEVICES_ON_DEVICE_INFO_CHANGE,
-                api::signed_in_devices::OnDeviceInfoChange::kEventName,
-                std::move(result)));
-
-  event->restrict_to_browser_context = profile_;
+  auto event = base::MakeUnique<Event>(
+      events::SIGNED_IN_DEVICES_ON_DEVICE_INFO_CHANGE,
+      api::signed_in_devices::OnDeviceInfoChange::kEventName, std::move(result),
+      profile_);
 
   EventRouter::Get(profile_)
       ->DispatchEventToExtension(extension_id_, std::move(event));
 }
 
 static base::LazyInstance<
     BrowserContextKeyedAPIFactory<SignedInDevicesManager>>::DestructorAtExit
     g_factory = LAZY_INSTANCE_INITIALIZER;
 
 // static
@@ skipping 62 matching lines @@
 }
 
 void SignedInDevicesManager::OnExtensionUnloaded(
     content::BrowserContext* browser_context,
     const Extension* extension,
     UnloadedExtensionReason reason) {
   RemoveChangeObserverForExtension(extension->id());
 }
 
 }  // namespace extensions