Allow comments in extension config files.

chrome/common/extensions/api/devtools_api.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": "devtools.inspectedWindow",
     "types": [
       {
         "id": "Resource",
         "type": "object",
         "description": "A resource within the inspected page, such as a document, a script, or an image.",
         "properties": {
           "url": {
@@ skipping 830 matching lines @@
             "type": "string"
           },
           "Severe": {
             "type": "string"
           }
         }
       }
     ]
   }
 ]