Only execute default actions on trusted events.

LayoutTests/fast/forms/range/slider-transformed.html

Index: LayoutTests/fast/forms/range/slider-transformed.html
diff --git a/LayoutTests/fast/forms/range/slider-transformed.html b/LayoutTests/fast/forms/range/slider-transformed.html
index 03f6222138667b626ad39ab4851fb100546dea68..de8317168e4bf7ddaa1f8d8c1078ac8054ec8347 100644
--- a/LayoutTests/fast/forms/range/slider-transformed.html
+++ b/LayoutTests/fast/forms/range/slider-transformed.html
@@ -17,19 +17,14 @@
     if (window.testRunner)
         testRunner.dumpAsText();
 
-    function dispatchEvent(eventType, clientX, clientY)
-    {
-      var ev = document.createEvent("MouseEvent");
-      ev.initMouseEvent(eventType, true, true, window, 1, 1, 1, clientX, clientY, false, false, false, false, 0, document);
-      var target = document.elementFromPoint(ev.clientX, ev.clientY);
-      target.dispatchEvent(ev);
-    }
-    
     function test()
     {
       // For some reason the slider needs mouseup/mousedown, not just a "click"
-      dispatchEvent("mousedown", 61, 71);
-      dispatchEvent("mouseup", 61, 71);
+      if (window.eventSender) {
+          eventSender.mouseMoveTo(61, 71);
+          eventSender.mouseDown(0);
+          eventSender.mouseUp(0);
+      }
 
       const expectedValue = 39;
       var val = document.getElementById('slider').value;
@@ -47,4 +42,4 @@
   <div id="results">
   </div>
 </body>
-</html>
+</html>