Simplify TestRunnerBindings::SimulateWebNotificationClick param handling

third_party/WebKit/LayoutTests/http/tests/notifications/resources/click-event-test.js

 if (self.importScripts) {
     importScripts('/resources/testharness.js');
     importScripts('worker-helpers.js');
 }
 
 async_test(function(test) {
     if (Notification.permission != 'granted') {
         assert_unreached('No permission has been granted for displaying notifications.');
         return;
     }
 
     var notification = new Notification('My Notification');
     notification.addEventListener('show', function() {
         if (testRunner)
-            testRunner.simulateWebNotificationClick('My Notification');
+            testRunner.simulateWebNotificationClick('My Notification', -1 /* action_index */);
     });
 
     notification.addEventListener('click', function() {
         test.done();
     });
 
     notification.addEventListener('error', function() {
         assert_unreached('The error event should not be thrown.');
     });
 
 }, 'Simulating a click on the notification should fire the onclick() event.');
 
 if (isDedicatedOrSharedWorker())
     done();