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

chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.cc

Index: chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.cc
diff --git a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.cc b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.cc
index 51f8450a761f792b32a2150bbebd409ef84a46ea..176a9e84c51eda4e92846555cc7e0b09892935fb 100644
--- a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.cc
+++ b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.cc
@@ -11,7 +11,6 @@
 #include "chrome/common/extensions/api/media_galleries_private.h"
 #include "content/public/browser/browser_thread.h"
 #include "extensions/browser/event_router.h"
-#include "extensions/browser/extension_system.h"
 
 namespace media_galleries_private = extensions::api::media_galleries_private;
 
@@ -34,8 +33,7 @@ void MediaGalleriesPrivateEventRouter::OnGalleryChanged(
     MediaGalleryPrefId gallery_id,
     const std::set<std::string>& extension_ids) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  EventRouter* router =
-      extensions::ExtensionSystem::Get(profile_)->event_router();
+  extensions::EventRouter* router = extensions::EventRouter::Get(profile_);

[not at google - send to devlin, 2014/04/17 16:09:46]

don't need extensions::

   if (!router->HasEventListener(
           media_galleries_private::OnGalleryChanged::kEventName))
     return;