Move Extension into extensions namespace

chrome/browser/extensions/api/commands/extension_command_service.h

Index: chrome/browser/extensions/api/commands/extension_command_service.h
diff --git a/chrome/browser/extensions/api/commands/extension_command_service.h b/chrome/browser/extensions/api/commands/extension_command_service.h
index 51ec0a100e99ea04361769aedafe943abb4a5f8e..1bb908b9e071d7acba496e27855149124b502267 100644
--- a/chrome/browser/extensions/api/commands/extension_command_service.h
+++ b/chrome/browser/extensions/api/commands/extension_command_service.h
@@ -88,7 +88,7 @@ class ExtensionCommandService : public ProfileKeyedService,
   // free, it will be taken by this extension. If not, that keybinding request
   // is ignored. |user_pref| is the PrefService used to record the new
   // keybinding assignment.
-  void AssignInitialKeybindings(const Extension* extension);
+  void AssignInitialKeybindings(const extensions::Extension* extension);
 
   // Removes all keybindings for a given extension by its |extension_id|.
   void RemoveKeybindingPrefs(std::string extension_id);