Move Extension into extensions namespace

chrome/browser/extensions/permissions_updater.h

Index: chrome/browser/extensions/permissions_updater.h
diff --git a/chrome/browser/extensions/permissions_updater.h b/chrome/browser/extensions/permissions_updater.h
index 0640f2d80a87df3f7199bc737baf1851d0330adb..863e620d5c9824fb22d543c329c87731c68d1926 100644
--- a/chrome/browser/extensions/permissions_updater.h
+++ b/chrome/browser/extensions/permissions_updater.h
@@ -10,16 +10,18 @@
 
 #include "base/memory/ref_counted.h"
 
-namespace base {
-class DictionaryValue;
-}
-class Extension;
 class ExtensionPermissionSet;
 class ExtensionPrefs;
 class Profile;
 
+namespace base {
+class DictionaryValue;
+}
+
 namespace extensions {
 
+class Extension;
+
 // Updates an Extension's active and granted permissions in persistent storage
 // and notifies interested parties of the changes.
 class PermissionsUpdater {