Don't force layout for mouse event hit tests

LayoutTests/fast/events/window-events-capture.html

Index: LayoutTests/fast/events/window-events-capture.html
diff --git a/LayoutTests/fast/events/window-events-capture.html b/LayoutTests/fast/events/window-events-capture.html
index 6d4b9249a9b4d017501e43d67006f4f26b853fe3..f2efb7ed156068b61a0570e328ff2f074bec60c6 100644
--- a/LayoutTests/fast/events/window-events-capture.html
+++ b/LayoutTests/fast/events/window-events-capture.html
@@ -9,6 +9,8 @@ if (window.testRunner) {
 function test()
 {
     if (window.eventSender) {
+        // Mouse events only work after an initial layout
+        document.body.offsetLeft;
         eventSender.mouseMoveTo(52, 52);
         eventSender.mouseDown();
         eventSender.mouseUp();
@@ -43,4 +45,4 @@ window.addEventListener("click", windowClick, true);
         
     <div id="result" style="position: absolute; top: 100; left: 50;"><br></div>
 </body>
-</html>
+</html>