[Extensions] Make Event::restrict_to_browser_context const.

chrome/browser/extensions/api/cookies/cookies_api.cc

 // Copyright (c) 2012 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.
 
 // Implements the Chrome Extensions Cookies API.
 
 #include "chrome/browser/extensions/api/cookies/cookies_api.h"
 
 #include <memory>
 #include <utility>
@@ skipping 175 matching lines @@
 
 void CookiesEventRouter::DispatchEvent(
     content::BrowserContext* context,
     events::HistogramValue histogram_value,
     const std::string& event_name,
     std::unique_ptr<base::ListValue> event_args,
     GURL& cookie_domain) {
   EventRouter* router = context ? EventRouter::Get(context) : NULL;
   if (!router)
     return;
-  std::unique_ptr<Event> event(
-      new Event(histogram_value, event_name, std::move(event_args)));
-  event->restrict_to_browser_context = context;
+  auto event = base::MakeUnique<Event>(histogram_value, event_name,
+                                       std::move(event_args), context);
   event->event_url = cookie_domain;
   router->BroadcastEvent(std::move(event));
 }
 
 CookiesGetFunction::CookiesGetFunction() {
 }
 
 CookiesGetFunction::~CookiesGetFunction() {
 }
 
@@ skipping 379 matching lines @@
 BrowserContextKeyedAPIFactory<CookiesAPI>* CookiesAPI::GetFactoryInstance() {
   return g_factory.Pointer();
 }
 
 void CookiesAPI::OnListenerAdded(const EventListenerInfo& details) {
   cookies_event_router_.reset(new CookiesEventRouter(browser_context_));
   EventRouter::Get(browser_context_)->UnregisterObserver(this);
 }
 
 }  // namespace extensions