private boolean isCollapsed(int offset) {
      while (foldRegion < myFoldRegions.length) {
        FoldRegion region = myFoldRegions[foldRegion];
        if (offset <= region.getStartOffset()) return false;
        if (offset <= region.getEndOffset()) return true;
        foldRegion++;
      }
      return false;
    }
private boolean isCollapsed(int offset)