Set up the infrastructure for Extension event metrics.

chrome/browser/extensions/api/web_navigation/web_navigation_api_helpers.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 WebNavigation API.
 
 #include "chrome/browser/extensions/api/web_navigation/web_navigation_api_helpers.h"
 
 #include "base/json/json_writer.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 30 matching lines @@
 void DispatchEvent(content::BrowserContext* browser_context,
                    const std::string& event_name,
                    scoped_ptr<base::ListValue> args,
                    const GURL& url) {
   EventFilteringInfo info;
   info.SetURL(url);
 
   Profile* profile = Profile::FromBrowserContext(browser_context);
   EventRouter* event_router = EventRouter::Get(profile);
   if (profile && event_router) {
-    scoped_ptr<Event> event(new Event(event_name, args.Pass()));
+    scoped_ptr<Event> event(
+        new Event(events::UNKNOWN, event_name, args.Pass()));
     event->restrict_to_browser_context = profile;
     event->filter_info = info;
     event_router->BroadcastEvent(event.Pass());
   }
 }
 
 }  // namespace
 
 int GetFrameId(content::RenderFrameHost* frame_host) {
   if (!frame_host)
@@ skipping 173 matching lines @@
 
   DispatchEvent(browser_context,
                 web_navigation::OnTabReplaced::kEventName,
                 args.Pass(),
                 GURL());
 }
 
 }  // namespace web_navigation_api_helpers
 
 }  // namespace extensions