Allow comments in extension config files.

chrome/common/extensions/api/types.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": "types",
     "types": [
       {
         "id": "ChromeSetting",
         "type": "object",
         "customBindings": "ChromeSetting",
         "description": "An interface which allows access to a Chrome browser setting.",
         "functions": [
@@ skipping 127 matching lines @@
                   }
                 }
               }
             ]
           }
         ]
       }
     ]
   }
 ]