Explicitly specify returning shadow roots from script

Author: jimevanssfdc

index.html

@@ -6415,6 +6415,10 @@ <h3>Executing Script</h3>
    <dd><p>Return the <a data-lt="deserialize a web element">deserialized</a>
     <a>web element</a> of <var>value</var>.
 
+   <dt><a>Object</a> that <a>represents a shadow root</a>
+   <dd><p>Return the <a data-lt="deserialize a shadow root">deserialized</a>
+    <a>shadow root</a> of <var>value</var>.
+
    <dt>instance of <a>Array</a>
    <dt>instance of <a>Object</a>
    <dd><p>Return the result of running the <a>clone an object</a> algorithm
@@ -6463,6 +6467,13 @@ <h3>Executing Script</h3>
   <p>Otherwise return <a>success</a> with data set to the <var>web
   element reference object</var> for <var>value</var>.
 
+ <dt>instance of <a>shadow root</a>
+ <dd><p>If the <var>shadow root</var> <a>is detached</a>,
+  return <a>error</a> with <a>error code</a> <a>detached shadow root</a>.
+
+  <p>Otherwise return <a>success</a> with data set to the <var>shadow
+  root reference object</var> for <var>value</var>.
+
  <dt>a <a><code>WindowProxy</code></a> object
  <dd><p>If the associated <a>browsing context</a>
   of the <a><code>WindowProxy</code></a> object