Updating JSON Schema Compiler to add description field to schemas.

tools/json_schema_compiler/test/idl_reserved_words.idl

 // 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.
 
+// Tests 'reserved words' in various places in IDL.
+
 namespace reserved_words {
 
   enum Foo { _float, _DOMString };
 
   enum _enum {
     _callback,
     _namespace
   };
 
   dictionary _dictionary {
     long _long;
   };
 
   dictionary MyType {
     DOMString _interface;
   };
 
   interface Functions {
     static void _static(Foo foo, _enum e);
   };
 };