[cssom] bug #18462 - remove duplicate text

Author: skynavga

cssom/Overview.html

@@ -1487,9 +1487,6 @@ <h4 id="requirements-on-user-agents-implementing-the-http-link-header"><span cla
      <dt><a href="#style-sheet-parent">style sheet parent</a></dt>
      <dd><p>null</dd>
 
-     <dt><a href="#style-sheet-owner-node">style sheet owner node</a></dt>
-     <dd><p>null</dd>
-
      <dt><a href="#style-sheet-owner-css-rule">style sheet owner CSS rule</a></dt>
      <dd><p>null</dd>
 

cssom/cssom-source

@@ -1267,9 +1267,6 @@
      <dt><span>style sheet parent</span></dt>
      <dd><p>null</p></dd>
 
-     <dt><span>style sheet owner node</span></dt>
-     <dd><p>null</p></dd>
-
      <dt><span>style sheet owner CSS rule</span></dt>
      <dd><p>null</p></dd>