Add ServiceWorker InstallPhaseEvent.waitUntil() layout test.

Source/modules/serviceworkers/WaitUntilObserver.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "modules/serviceworkers/WaitUntilObserver.h"
 
 #include "bindings/core/v8/ScriptFunction.h"
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptValue.h"
@@ skipping 44 matching lines @@
     ResolveType m_resolveType;
 };
 
 PassRefPtr<WaitUntilObserver> WaitUntilObserver::create(ExecutionContext* context, EventType type, int eventID)
 {
     return adoptRef(new WaitUntilObserver(context, type, eventID));
 }
 
 WaitUntilObserver::~WaitUntilObserver()
 {
-    ASSERT(!m_pendingActivity);
 }
 
 void WaitUntilObserver::willDispatchEvent()
 {
     incrementPendingActivity();
 }
 
 void WaitUntilObserver::didDispatchEvent()
 {
     decrementPendingActivity();
@@ skipping 25 matching lines @@
 }
 
 void WaitUntilObserver::incrementPendingActivity()
 {
     ++m_pendingActivity;
 }
 
 void WaitUntilObserver::decrementPendingActivity()
 {
     ASSERT(m_pendingActivity > 0);
-    if (--m_pendingActivity || !executionContext())
+    if (!executionContext() || (!m_hasError && --m_pendingActivity))
         return;
 
     ServiceWorkerGlobalScopeClient* client = ServiceWorkerGlobalScopeClient::from(executionContext());
     blink::WebServiceWorkerEventResult result = m_hasError ? blink::WebServiceWorkerEventResultRejected : blink::WebServiceWorkerEventResultCompleted;
     switch (m_type) {
     case Activate:
         client->didHandleActivateEvent(m_eventID, result);
         break;
     case Install:
         client->didHandleInstallEvent(m_eventID, result);
         break;
     }
     observeContext(0);
 }
 
 } // namespace WebCore