message: add comment - explain conditional statusBar
diff: @@ -1852,6 +1852,8 @@ export default class RoomView extends React.Component<IProps, IState> {
  "mx_RoomView_statusArea_expanded": isStatusAreaExpanded,
  });
  + // if statusBar does not exist then statusBarArea is blank and takes up unnecessary space on the screen
  + // show statusBarArea only if statusBar is present
  const statusBarArea = statusBar && <div className={statusBarAreaClass}>
  <div className="mx_RoomView_statusAreaBox">
  <div className="mx_RoomView_statusAreaBox_line" />
  