Cleanup: remove the namespace-level nodoc annotations from Extension API

chrome/common/extensions/api/principals_private.idl

 // Copyright 2013 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.
 
 // Experimental APIs to trigger Chrome sign in actions.
 // Only enabled if the flag "new-profile-management" is set.
-[nodoc] namespace principalsPrivate {
+namespace principalsPrivate {
 
   interface Functions {
     // Triggers Chrome sign out.
     // Only enabled if the flag "new-profile-management" is set.
     static void signOut();
 
     // Shows the avatar bubble.
     // Only enabled if the flag "new-profile-management" is set.
     static void showAvatarBubble();
   };
 };