[ServiceWorker] Allow waitUntil to be called multiple times asynchronously

third_party/WebKit/Source/modules/serviceworkers/WaitUntilObserver.h

 // 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.
 
 #ifndef WaitUntilObserver_h
 #define WaitUntilObserver_h
 
 #include "modules/ModulesExport.h"
 #include "modules/serviceworkers/ServiceWorkerGlobalScopeClient.h"
 #include "platform/Timer.h"
@@ skipping 36 matching lines @@
   // all waitUntil promises to settle.
   void DidDispatchEvent(bool event_dispatch_failed);
 
   // Observes the promise and delays calling the continuation until
   // the given promise is resolved or rejected.
   void WaitUntil(ScriptState*, ScriptPromise, ExceptionState&);
 
   // These methods can be called when the lifecycle of ExtendableEvent
   // observed by this WaitUntilObserver should be extended by other reason
   // than ExtendableEvent.waitUntil.
-  // Note: There is no need to call decrementPendingActivity() after the context
+  // Note: There is no need to call DecrementPendingPromise() after the context
   // is being destroyed.
-  void IncrementPendingActivity();
-  void DecrementPendingActivity();
+  void IncrementPendingPromise();
+  void DecrementPendingPromise();
 
   DECLARE_VIRTUAL_TRACE();
 
  private:
   friend class InternalsServiceWorker;
   class ThenFunction;
 
   enum class EventDispatchState {
-    // Event dispatch has not yet finished.
+    // Event dispatch has not yet started.
     kInitial,
+    // Event dispatch has started but not yet finished.
+    kDispatching,
     // Event dispatch completed. There may still be outstanding waitUntil
     // promises that must settle before notifying ServiceWorkerGlobalScopeClient
     // that the event finished.
-    kCompleted,
+    kDispatched,
     // Event dispatch failed. Any outstanding waitUntil promises are ignored.
     kFailed
   };
 
   WaitUntilObserver(ExecutionContext*, EventType, int event_id);
 
   // Called when a promise passed to a waitUntil() call that is associated with
   // this observer was fulfilled.
   void OnPromiseFulfilled();
   // Called when a promise passed to a waitUntil() call that is associated with
   // this observer was rejected.
   void OnPromiseRejected();
 
   void ConsumeWindowInteraction(TimerBase*);
 
+  void MaybeCompleteEvent();
+
   Member<ExecutionContext> execution_context_;
   EventType type_;
   int event_id_;
-  int pending_activity_ = 0;
+  int pending_promise_ = 0;

[falken, 2017/05/24 08:24:18]

pending_promises_

[leonhsl(Using Gerrit), 2017/05/25 00:16:40]

Done.

   EventDispatchState event_dispatch_state_ = EventDispatchState::kInitial;
   bool has_rejected_promise_ = false;
   double event_dispatch_time_ = 0;
   TaskRunnerTimer<WaitUntilObserver> consume_window_interaction_timer_;
 };
 
 }  // namespace blink
 
 #endif  // WaitUntilObserver_h