Cleanup: fix Namespace comments in /extension/commons

extensions/common/dom_action_types.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef EXTENSIONS_COMMON_DOM_ACTION_TYPES_H_
 #define EXTENSIONS_COMMON_DOM_ACTION_TYPES_H_
 
 namespace extensions {
 
 struct DomActionType {
   // These values should not be changed. Append any additional values to the
   // end with sequential numbers.
   enum Type {
     GETTER = 0,      // For Content Script DOM manipulations
     SETTER = 1,      // For Content Script DOM manipulations
     METHOD = 2,      // For Content Script DOM manipulations
     INSERTED = 3,    // For when Content Scripts are added to pages
     XHR = 4,         // When an extension core sends an XHR
     WEBREQUEST = 5,  // When a page request is modified with the WebRequest API
     MODIFIED = 6,    // For legacy, also used as a catch-all
   };
 };
 
-}  // namespace
+}  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_DOM_ACTION_TYPES_H_