The Tor Browser / file revision

 /**

  * Any copyright is dedicated to the Public Domain.

  * http://creativecommons.org/publicdomain/zero/1.0/

  */

 var data = [ -1, 0, 1, 1.5, /* null ,*/ undefined, true, false, "foo",

              "123456789012345", "1234567890123456", "12345678901234567"];

 var str = "";

 for (var i = 0; i < 30; i++) {

   data.push(str);

   str += i % 2 ? "b" : "a";

 }

 onmessage = function(event) {

   data.forEach(function(string) {

     var encoded = btoa(string);

     postMessage({ type: "btoa", value: encoded });

     postMessage({ type: "atob", value: atob(encoded) });

   });

   var threw;

   try {

     atob();

   }

   catch(e) {

     threw = true;

   }

   if (!threw) {

     throw "atob didn't throw when called without an argument!";

   }

   threw = false;

   try {

     btoa();

   }

   catch(e) {

     threw = true;

   }

   if (!threw) {

     throw "btoa didn't throw when called without an argument!";

   }

   postMessage({ type: "done" });

 }