Avoid setting target to the Window object

fc16564 did not adequately consider the global object.

Fixes #697.

Author: annevk

dom.bs

@@ -1271,8 +1271,9 @@ for discussion).
      <var>touchTarget</var> against <var>parent</var> to <var>touchTargets</var>.
 
      <li>
-      <p>If <var>parent</var> is a <a>node</a> and <var>target</var>'s <a for=tree>root</a> is a
-      <a>shadow-including inclusive ancestor</a> of <var>parent</var>, then:
+      <p>If <var>parent</var> is a {{Window}} object, or <var>parent</var> is a <a>node</a> and
+      <var>target</var>'s <a for=tree>root</a> is a <a>shadow-including inclusive ancestor</a> of
+      <var>parent</var>, then:
 
       <ol>
        <li><p>If <var>isActivationEvent</var> is true, <var>event</var>'s {{Event/bubbles}}