The second argument of add/removeEventListener should be an object, null, or undefined

third_party/WebKit/LayoutTests/fast/events/onclick-list-marker.html

 <script>
 var clicks = 0;
 var console = document.getElementById('console');
 var x, y;
 
 function log(message) {
     var console = document.getElementById('console');
     var text = document.createTextNode(message);
     console.appendChild(text);
     console.appendChild(document.createElement("br"));
@@ skipping 43 matching lines @@
     eventSender.mouseMoveTo(x, y);
     eventSender.mouseDown();
     eventSender.mouseUp();
 
     li.style.listStylePosition = "outside";
     // WebCore renders an outside list marker at offsetLeft minus an offset, which is equal on a
     // magic number, 7, plus the ascent of the font * 2/3.  Since we can't get the ascent from JS, just make sure that
     // the list marker is hit at some point between the left edge of the list item and the left edge of the list.
     
     li.onclick = clickCounter;
-    ul.onclick = 0;
+    ul.onclick = null;
     
     for (x = ul.offsetLeft; x < li.offsetLeft; x += 5) {
         eventSender.mouseMoveTo(x, y);
         eventSender.mouseDown();
         eventSender.mouseUp();   
     }
     
     if (clicks == 0)
         log("Failure, the list marker wasn't hit during any of the mouse clicks between the left edge of the list item and the left edge of the list.");
 }
@@ skipping 21 matching lines @@
 <ul id="ul" onclick="clickHandler('ul');">
 <li id="li" onclick="clickHandler('li');"><span id="span" onclick="clickHandler('span')">text</span></li>
 </ul>
 
 <p>This is a testcase for hit testing over list markers.  It uses the eventSender to do mouse clicks and programmatically adjusts the left margin of the span inside the list item and the list-style-position: of the list item.</p>
 
 <p id="console"></p>
 
 <script>
 runTest();
-</script>
+</script>