function parentHasNoTextContent(node) {
    if (nodeHelpers.isCaretPositionNode(node)) {
      return true;
    } else {
      return node.parentNode.textContent.trim() === '';
    }
  }
Chrome and Firefox: All elements need to contain either text or a `<br>` to
remain selectable. (Unless they have a width and height explicitly set with
CSS(?), as per: http://jsbin.com/gulob/2/edit?html,css,js,output)