[delete-to-join-blocks.tentative.html]
  [document.execCommand("delete") when "<div>a<div>[\]&nbsp;&nbsp;&nbsp;b</div></div>"]
    expected: FAIL

  [document.execCommand("delete") when "<div>a&nbsp;&nbsp;&nbsp;<div>[\]&nbsp;&nbsp;&nbsp;b</div></div>"]
    expected: FAIL

  [document.execCommand("delete") when "<div><div><br></div>[\]&nbsp;&nbsp;&nbsp;</div>"]
    expected: FAIL

  [document.execCommand("delete") when "<div><div><br></div>[\]&nbsp;&nbsp;&nbsp;b</div>"]
    expected: FAIL

  [document.execCommand("delete") when "<div><div>a</div>[\]&nbsp;&nbsp;&nbsp;b</div>"]
    expected: FAIL

  [document.execCommand("delete") when "<div><div>a&nbsp;&nbsp;&nbsp;</div>[\]&nbsp;&nbsp;&nbsp;b</div>"]
    expected: FAIL