Allow comments in extension config files.

chrome/common/extensions/api/browsingData.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": "browsingData",
     "types": [
       {
         "id": "RemovalOptions",
         "type": "object",
         "description": "Options that determine exactly what data will be removed.",
         "properties": {
           "since": {
@@ skipping 307 matching lines @@
             "type": "function",
             "description": "Called when websites' WebSQL databases have been cleared.",
             "optional": true,
             "parameters": []
           }
         ]
       }
     ]
   }
 ]