Moved the AppNotification system into extensions namespace

chrome/browser/extensions/app_notification.h

Index: chrome/browser/extensions/app_notification.h
diff --git a/chrome/browser/extensions/app_notification.h b/chrome/browser/extensions/app_notification.h
index 97a39d54ab569cb5ebcc3fadaf38650e28ed53fa..9218bdc90f0aea180c16346ade60da22d71e0172 100644
--- a/chrome/browser/extensions/app_notification.h
+++ b/chrome/browser/extensions/app_notification.h
@@ -13,6 +13,8 @@
 #include "base/values.h"
 #include "googleurl/src/gurl.h"
 
+namespace extensions {
+
 // This class is used to represent a notification for an installed app, to be
 // displayed on the New Tab Page.
 class AppNotification {
@@ -84,4 +86,6 @@ typedef std::vector<linked_ptr<AppNotification> > AppNotificationList;
 // Caller owns the returned instance.
 AppNotificationList* CopyAppNotificationList(const AppNotificationList& source);
 
+}  // namespace extensions
+
 #endif  // CHROME_BROWSER_EXTENSIONS_APP_NOTIFICATION_H_