Set up the infrastructure for Extension event metrics.

chrome/browser/extensions/api/extension_action/extension_action_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.
 
 #include "chrome/browser/extensions/api/extension_action/extension_action_api.h"
 
 #include "base/lazy_instance.h"
 #include "base/location.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 287 matching lines @@
 }
 
 void ExtensionActionAPI::DispatchEventToExtension(
     content::BrowserContext* context,
     const std::string& extension_id,
     const std::string& event_name,
     scoped_ptr<base::ListValue> event_args) {
   if (!EventRouter::Get(context))
     return;
 
-  scoped_ptr<Event> event(new Event(event_name, event_args.Pass()));
+  scoped_ptr<Event> event(
+      new Event(events::UNKNOWN, event_name, event_args.Pass()));
   event->restrict_to_browser_context = context;
   event->user_gesture = EventRouter::USER_GESTURE_ENABLED;
   EventRouter::Get(context)
       ->DispatchEventToExtension(extension_id, event.Pass());
 }
 
 void ExtensionActionAPI::ExtensionActionExecuted(
     const ExtensionAction& extension_action,
     WebContents* web_contents) {
   const char* event_name = NULL;
@@ skipping 357 matching lines @@
   if (host->extension_host_type() != VIEW_TYPE_EXTENSION_POPUP ||
       host->extension()->id() != extension_->id())
     return;
 
   SendResponse(true);
   response_sent_ = true;
   registrar_.RemoveAll();
 }
 
 }  // namespace extensions