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

chrome/common/extensions/api/chromeos_info_private.json

 // Copyright (c) 2012 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.
 
 [
   {
     "namespace": "chromeosInfoPrivate",
     "description": "none",
     "compiler_options": {
       "implemented_in": "chrome/browser/chromeos/extensions/info_private_api.h"
     },
     "platforms": ["chromeos"],
-    "nodoc": "true",
     "functions": [
       {
         "name": "get",
         "description": "Fetches customization values for the given property names. See property names in the declaration of the returned dictionary.",
         "type": "function",
         "parameters": [
           {
             "name": "propertyNames",
             "type": "array",
             "description": "Chrome OS Property names",
@@ skipping 61 matching lines @@
           {
             "name": "propertyValue",
             "type": "any",
             "description": "Chrome OS system property value"
           }
         ]
       }
     ]
   }
 ]