cleanup: Use EventRouter instead of ExtensionSystem::Get->event_router()

chrome/browser/extensions/api/extension_action/extension_action_api.cc

Index: chrome/browser/extensions/api/extension_action/extension_action_api.cc
diff --git a/chrome/browser/extensions/api/extension_action/extension_action_api.cc b/chrome/browser/extensions/api/extension_action/extension_action_api.cc
index d3f003e2ae769296288ade11c250853c5b6ad2db..4925b68e5dff9ee7924bf172a2db99535890de98 100644
--- a/chrome/browser/extensions/api/extension_action/extension_action_api.cc
+++ b/chrome/browser/extensions/api/extension_action/extension_action_api.cc
@@ -350,14 +350,14 @@ void ExtensionActionAPI::DispatchEventToExtension(
     const std::string& extension_id,
     const std::string& event_name,
     scoped_ptr<base::ListValue> event_args) {
-  if (!extensions::ExtensionSystem::Get(context)->event_router())
+  if (!extensions::EventRouter::Get(context))
     return;
 
   scoped_ptr<Event> event(new Event(event_name, event_args.Pass()));
   event->restrict_to_browser_context = context;
   event->user_gesture = EventRouter::USER_GESTURE_ENABLED;
-  ExtensionSystem::Get(context)->event_router()->DispatchEventToExtension(
-      extension_id, event.Pass());
+  EventRouter::Get(context)
+      ->DispatchEventToExtension(extension_id, event.Pass());
 }
 
 // static