Revert "RBS: Pathname#taint and Pathname#untaint are removed"
This reverts commit 46132e78b7438389bf49a860a0cd8957f685dcb3, in favor of 298cb57c115e789c021962c758eb734c2d8ee1f6.
Revert "RBS: Pathname#taint and Pathname#untaint are removed"
This reverts commit 46132e78b7438389bf49a860a0cd8957f685dcb3, in favor
of 298cb57c115e789c021962c758eb734c2d8ee1f6.