Add NotificationOptions.actions so websites can provide buttons (blink)

Source/modules/notifications/Notification.idl

Index: Source/modules/notifications/Notification.idl
diff --git a/Source/modules/notifications/Notification.idl b/Source/modules/notifications/Notification.idl
index 0ad1096f9b3577e8cbf72eccec2bf20c9eec53bb..4435e926299c3692b53ddbfb5d0d717474fdb6a1 100644
--- a/Source/modules/notifications/Notification.idl
+++ b/Source/modules/notifications/Notification.idl
@@ -56,9 +56,13 @@
     readonly attribute DOMString tag;
     readonly attribute DOMString icon;
 
+    // TODO(johnme): Make this a FrozenArray instead before shipping.

[Peter Beverloo, 2015/07/30 16:24:08]

Bug?

[johnme, 2015/07/31 15:10:10]

No, but removed and tweaked TODO below since experimentally sequence seems to
behave as a deeply frozen FrozenArray already :-s

     [RuntimeEnabled=NotificationExperimental] readonly attribute sequence<unsigned long>? vibrate;
     readonly attribute boolean silent;
     [CallWith=ScriptState] readonly attribute any data;
 
+    // TODO(johnme): Make this a FrozenArray instead before shipping.
+    [RuntimeEnabled=NotificationExperimental] readonly attribute sequence<NotificationAction> actions;
+
     [MeasureAs=NotificationClosed] void close();
 };