UserAgent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:54.0) Gecko/20100101 Firefox/54.0

Steps to reproduce the problem:
1. StyleSheet |media|, CSSPageRule |style| IDL attribute should have [PutForwards]
2. 
3. 

What is the expected behavior?

What went wrong?
StyleSheet |media| should have [PutForwards=mediaText] and CSSPageRule |style| should have [PutForwards=cssText] as per the specification.
https://drafts.csswg.org/cssom/#the-stylesheet-interface
https://drafts.csswg.org/cssom/#the-csspagerule-interface

Did this work before? N/A 

Does this work in other browsers? N/A

Chrome version: <Copy from: 'about:version'>  Channel: n/a
OS Version: 
Flash Version: Shockwave Flash 10.1 r999.<br>Gnash 0.8.11dev, the GNU SWF Player.   Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011   <a href="http://www.fsf.org">Free   Software Foundation</a>, Inc. <br>   Gnash comes with NO WARRANTY, to the extent permitted by law.   You may redistribute copies of Gnash under the terms of the   <a href="http://www.gnu.org/licenses/gpl.html">GNU General Public   License</a>. For more information about Gnash, see <a   href="http://www.gnu.org/software/gnash/">   http://www.gnu.org/software/gnash</a>.   <br>  Compatible Shockwave Flash 10.1 r999.