ibute");
          next();
        });
    });
  },
  function() {
    v.src = "/media/sound_0.mp3";
    // Source should be ignored when there is an `src`
    let sourceNode = document.createElement("source");
    sourceNode.setAttribute("src", "/media/sine440.mp3");
    sourceNode.setAttribute("type", "audio/mpeg");
    v.appendChild(sourceNode);
    queueTaskAndStep(function() {
      assert_true(v.currentSrc.indexOf("sine440.mp3") == -1, "The src attribute takes precedence over any source child element 