code: function insertLineWidgets(lineView, dims) {
      insertLineWidgetsFor(lineView.line, lineView, dims, true);
      if (lineView.rest) for (var i = 0; i < lineView.rest.length; i++)
        insertLineWidgetsFor(lineView.rest[i], lineView, dims, false);
    }
docs: A lineView may contain multiple logical lines (when merged by collapsed spans). The widgets for all of them need to be drawn.