Only allow action buttons in persistent notifications per spec update

third_party/WebKit/Source/modules/notifications/Notification.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 61 matching lines @@
         exceptionState.throwTypeError("Illegal constructor. Use ServiceWorkerRegistration.showNotification() instead.");
         return nullptr;
     }
 
     // The Web Notification constructor may not be used in Service Worker contexts.
     if (context->isServiceWorkerGlobalScope()) {
         exceptionState.throwTypeError("Illegal constructor.");
         return nullptr;
     }
 
+    if (!options.actions().isEmpty()) {

[Peter Beverloo, 2015/10/21 17:02:52]

It's unfortunate that the place in the algorithm you chose to insert the
`actions` steps in makes it hard or us to support it in order.

Per the spec:
  (1) Check for `silent` & `vibrate`/`sound`, throw if invalid.
  (2) Check for `renotify` & `tag`, throw if invalid.
  (3) Check for `actions` and persistent, throw if invalid.
  ...

Implementation:
  (1) Check for `action` and persistent, throw if invalid.
  (2) Check for `silent` & `vibrate`/`sound`, throw if invalid.
  ...

This is Web-observable behaviour and could cause discrepancies between
implementations, but I'm not sure how much to care. It's certainly not worth
giving createWebNotificationData knowledge of the type of notification.

[johnme, 2015/10/21 18:11:31]

Hmm yeah, and we can't even move this check after createWebNotificationData
because then it would incorrectly occur after the "Set notification’s data to a
structured clone of options’s data. Rethrow any exceptions." step.

I've updated my spec patch to re-order these.

+        exceptionState.throwTypeError("Actions are only supported for persistent notifications shown using ServiceWorkerRegistration.showNotification().");
+        return nullptr;
+    }
+
     String insecureOriginMessage;
     UseCounter::Feature feature = context->isSecureContext(insecureOriginMessage)
         ? UseCounter::NotificationSecureOrigin
         : UseCounter::NotificationInsecureOrigin;
 
     UseCounter::count(context, feature);
 
     WebNotificationData data = createWebNotificationData(context, title, options, exceptionState);
     if (exceptionState.hadException())
         return nullptr;
@@ skipping 266 matching lines @@
     return m_state == NotificationStateShowing || m_asyncRunner.isActive();
 }
 
 DEFINE_TRACE(Notification)
 {
     RefCountedGarbageCollectedEventTargetWithInlineData<Notification>::trace(visitor);
     ActiveDOMObject::trace(visitor);
 }
 
 } // namespace blink