Use unique_ptr for Create{ServiceWorkerNetworkProvider,ApplicationCacheHost}

third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h

 /*
  * 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 220 matching lines @@
                                   WebServiceWorkerEventResult result,
                                   double event_dispatch_time) {}
 
   // ServiceWorker specific method. Called after PaymentRequestEvent (dispatched
   // via WebServiceWorkerContextProxy) is handled by the ServiceWorker's script
   // context.
   virtual void DidHandlePaymentRequestEvent(int payment_request_event_id,
                                             WebServiceWorkerEventResult result,
                                             double event_dispatch_time) {}
 
   // Ownership of the returned object is transferred to the caller.

[nhiroki, 2017/05/01 05:04:28]

ditto.

   // This is called on the main thread.
-  virtual WebServiceWorkerNetworkProvider*
-  CreateServiceWorkerNetworkProvider() {
-    return nullptr;
-  }
+  virtual std::unique_ptr<WebServiceWorkerNetworkProvider>
+  CreateServiceWorkerNetworkProvider() = 0;
 
   // Creates a WebWorkerFetchContext for a service worker. Ownership of the
   // returned object is transferred to the caller. This is called on the main
   // thread. This is used only when off-main-thread-fetch is enabled.
   virtual std::unique_ptr<blink::WebWorkerFetchContext>
   CreateServiceWorkerFetchContext() {
     return nullptr;
   }
 
   // Ownership of the returned object is transferred to the caller.

[nhiroki, 2017/05/01 05:04:27]

ditto.

   // This is called on the main thread.
-  virtual WebServiceWorkerProvider* CreateServiceWorkerProvider() {
-    return nullptr;
-  }
+  virtual std::unique_ptr<WebServiceWorkerProvider>
+  CreateServiceWorkerProvider() = 0;
 
   // Ownership of the passed callbacks is transferred to the callee, callee
   // should delete the callbacks after calling either onSuccess or onError.
   // WebServiceWorkerClientInfo and WebServiceWorkerError ownerships are
   // passed to the WebServiceWorkerClientCallbacks implementation.
   virtual void GetClient(const WebString&,
                          std::unique_ptr<WebServiceWorkerClientCallbacks>) = 0;
 
   // Ownership of the passed callbacks is transferred to the callee, callee
   // should delete the callbacks after calling either onSuccess or onError.
@@ skipping 50 matching lines @@
   // Called when the worker wants to register subscopes to handle via foreign
   // fetch. Will only be called while an install event is in progress.
   virtual void RegisterForeignFetchScopes(
       const WebVector<WebURL>& sub_scopes,
       const WebVector<WebSecurityOrigin>& origins) = 0;
 };
 
 }  // namespace blink
 
 #endif  // WebServiceWorkerContextClient_h