The Tor Browser / file revision

 const Cu = Components.utils;

 function run_test() {

   var sb = new Cu.Sandbox('http://www.example.com');

   var obj = Cu.evalInSandbox('this.obj = {foo: 2}; obj', sb);

   var chromeSb = new Cu.Sandbox(this);

   chromeSb.objRef = obj;

   do_check_eq(Cu.evalInSandbox('objRef.foo', chromeSb), 2);

   Cu.nukeSandbox(sb);

   do_check_true(Cu.isDeadWrapper(obj));

   // CCWs to nuked wrappers should be considered dead.

   do_check_true(Cu.isDeadWrapper(chromeSb.objRef));

 }