NavigationAction should not retain Event.

LayoutTests/resources/leak-check.js

 // include resources/js-test.js before this file.
 
+function getCounterValues() {
+    testRunner.resetTestHelperControllers();
+    gc();
+
+    var ret = {'numberOfLiveDocuments': window.internals.numberOfLiveDocuments()};
+
+    var refCountedInstances = JSON.parse(window.internals.dumpRefCountedInstanceCounts());
+    for (typename in refCountedInstances)
+        ret['numberOfInstances-'+typename] = refCountedInstances[typename];
+
+    return ret;
+}
+
+function compareValues(countersBefore, countersAfter, tolerance) {
+    for (type in tolerance) {
+        var before = countersBefore[type];
+        var after = countersAfter[type];
+
+        if (after - before <= tolerance[type])
+            testPassed('The difference of counter "'+type+'" before and after the cycle is under the threshold of '+tolerance[type]+'.');
+        else
+            testFailed('counter "'+type+'" was '+before+' before and now '+after+' after the cycle. This exceeds the threshold of '+tolerance[type]+'.');
+    }
+}
+
 function doLeakTest(src, tolerance) {
-    function getCounterValues() {
-        testRunner.resetTestHelperControllers();
-        gc();
-
-        var ret = {'numberOfLiveDocuments': window.internals.numberOfLiveDocuments()};
-
-        var refCountedInstances = JSON.parse(window.internals.dumpRefCountedInstanceCounts());
-        for (typename in refCountedInstances)
-            ret['numberOfInstances-'+typename] = refCountedInstances[typename];
-
-        return ret;
-    }
-
     var frame = document.createElement('iframe');
     document.body.appendChild(frame);
     function loadSourceIntoIframe(src, callback) {
         var originalSrc = frame.src;
 
         frame.onload = function() {
             if (frame.src === originalSrc)
                 return true;
 
             callback();
             return true;
         };
         frame.src = src;
     }
 
-    function compareValues(countersBefore, countersAfter, tolerance) {
-        for (type in tolerance) {
-            var before = countersBefore[type];
-            var after = countersAfter[type];
-
-            if (after - before <= tolerance[type])
-                testPassed('The difference of counter "'+type+'" before and after the cycle is under the threshold of '+tolerance[type]+'.');
-            else
-                testFailed('counter "'+type+'" was '+before+' before and now '+after+' after the cycle. This exceeds the threshold of '+tolerance[type]+'.');
-        }
-    }
-
     jsTestIsAsync = true;
     if (!window.internals) {
         debug("This test only runs on DumpRenderTree, as it requires existence of window.internals and cross-domain resource access check disabled.");
         finishJSTest();
     }
 
     loadSourceIntoIframe('about:blank', function() {
         // blank document loaded...
         var countersBefore = getCounterValues();
 
@@ skipping 18 matching lines @@
 
 function htmlToUrl(html) {
     return 'data:text/html;charset=utf-8,' + html;
 }
 
 function grabScriptText(id) {
     return document.getElementById(id).innerText;
 }
 
 // include fast/js/resources/js-test-post.js after this file.