Set up the infrastructure for Extension event metrics.

chrome/browser/extensions/api/sync_file_system/extension_sync_event_observer.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.
 
 #include "chrome/browser/extensions/api/sync_file_system/extension_sync_event_observer.h"
 
 #include "base/lazy_instance.h"
 #include "chrome/browser/extensions/api/sync_file_system/sync_file_system_api_helpers.h"
 #include "chrome/browser/sync_file_system/sync_event_observer.h"
 #include "chrome/browser/sync_file_system/sync_file_system_service.h"
@@ skipping 107 matching lines @@
 void ExtensionSyncEventObserver::BroadcastOrDispatchEvent(
     const GURL& app_origin,
     const std::string& event_name,
     scoped_ptr<base::ListValue> values) {
   // Check to see whether the event should be broadcasted to all listening
   // extensions or sent to a specific extension ID.
   bool broadcast_mode = app_origin.is_empty();
   EventRouter* event_router = EventRouter::Get(browser_context_);
   DCHECK(event_router);
 
-  scoped_ptr<Event> event(new Event(event_name, values.Pass()));
+  scoped_ptr<Event> event(
+      new Event(events::UNKNOWN, event_name, values.Pass()));
   event->restrict_to_browser_context = browser_context_;
 
   // No app_origin, broadcast to all listening extensions for this event name.
   if (broadcast_mode) {
     event_router->BroadcastEvent(event.Pass());
     return;
   }
 
   // Dispatch to single extension ID.
   const std::string extension_id = GetExtensionId(app_origin);
   if (extension_id.empty())
     return;
   event_router->DispatchEventToExtension(extension_id, event.Pass());
 }
 
 template <>
 void BrowserContextKeyedAPIFactory<
     ExtensionSyncEventObserver>::DeclareFactoryDependencies() {
   DependsOn(sync_file_system::SyncFileSystemServiceFactory::GetInstance());
   DependsOn(ExtensionsBrowserClient::Get()->GetExtensionSystemFactory());
 }
 
 }  // namespace extensions