The Tor Browser / file revision

 // test that things that are expected to be in gre-resources are still there

 var ios = Cc["@mozilla.org/network/io-service;1"]. getService(Ci.nsIIOService);

 function wrapInputStream(input)

 {

   var nsIScriptableInputStream = Components.interfaces.nsIScriptableInputStream;

   var factory = Components.classes["@mozilla.org/scriptableinputstream;1"];

   var wrapper = factory.createInstance(nsIScriptableInputStream);

   wrapper.init(input);

   return wrapper;

 }

 function check_file(file) {

   var channel = ios.newChannel("resource://gre-resources/"+file, null, null);

   try {

     let instr = wrapInputStream(channel.open());

     do_check_true(instr.read(1024).length > 0)

   } catch (e) {

     do_throw("Failed to read " + file + " from gre-resources:"+e)

   }

 }

 function run_test() {

   for each(let file in ["charsetData.properties"])

     check_file(file)

 }