Simplify TestRunnerBindings::SimulateWebNotificationClick param handling

third_party/WebKit/LayoutTests/http/tests/notifications/resources/worker-helpers.js

 var _port = self;
 
 // Returns whether the test is being ran in a dedicated or a shared worker. The
 // testharness.js framework requires done() to be called when this is the case.
 function isDedicatedOrSharedWorker()
 {
     return self.importScripts && !self.scope;
 }
 
 // Shared Workers will receive their message port once the first page connects to it.
 self.addEventListener('connect', function(event) {
     _port = event.ports[0];
 });
 
 var testRunner = {
-    simulateWebNotificationClick: function(title)
+    simulateWebNotificationClick: function(title, action_index)
     {
         if (_port)
-            _port.postMessage({ type: 'simulateWebNotificationClick', title: title });
+            _port.postMessage({ type: 'simulateWebNotificationClick', title: title, action_index: action_index });
     }
 };