Bug 740769. (Av1) Fix multiple issues in test_bug325418.js. r=bzbarsky.

const expected_time = 1;

var observer = {

  observe: function(subject, topic, data) {

  observe: function observeTC(subject, topic, data) {

    if (topic == "timer-callback") {

      var stop_time = (new Date()).getTime();

      timer.cancel();

      timer = null;

      // expected time may not be exact so convert to seconds and round down.

      var result = Math.round((stop_time - start_time) / 1000);

      do_check_true(result, expected_time);

      var result = Math.floor(((new Date()).getTime() - start_time) / 1000);

      do_check_eq(result, expected_time);

      do_test_finished();

      timer.cancel();

      timer = null;

    }

  }

};