For issue #850 - Remap ERR_UNSUPPORTED_ENCODING to NOT_READABLE_ERR. Mapped ERR_UNSUPPORTED_ENCODING to NOT_READABLE_ERR instead of SECURITY_ERR.
Merge pull request #2639 from connork09/850

Fixed issue #850 - Remap ERR_UNSUPPORTED_ENCODING to NOT_READABLE_ERR.