ediaSource)
          {
              mediaElement.addEventListener("error", test.unreached_func("Unexpected event 'error'"));
              MediaSourceUtil.fetchManifestAndData(test, manifestFilenameVideo, function (typeVideo, dataVideo)
              {
                  var sourceBuffer = mediaSource.addSourceBuffer(typeVideo);
                  assert_equals(mediaSource.sourceBuffers.length, 1,
                    "sourceBuffers list contains one SourceBuffer");
                  assert_equals(mediaSourc