CallbackPromiseAdapter types should be more compatible with WebCallbacks (3/3).

public/platform/modules/push_messaging/WebPushProvider.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 WebPushProvider_h
 #define WebPushProvider_h
 
 #include "public/platform/WebCallbacks.h"
 #include "public/platform/modules/push_messaging/WebPushPermissionStatus.h"
 
 namespace blink {
 
 class WebServiceWorkerRegistration;
 struct WebPushError;
 struct WebPushSubscription;
 struct WebPushSubscriptionOptions;
 
 using WebPushSubscriptionCallbacks = WebCallbacks<WebPushSubscription*, WebPushError*>;
 using WebPushPermissionStatusCallbacks = WebCallbacks<WebPushPermissionStatus*, WebPushError*>;

[Peter Beverloo, 2015/07/27 17:30:09]

Why can't we use const WebPushError& for these two callbacks? That'd allow us to
get rid of a few more *s in push code.

(Happy to take care of this later.)

[yhirano, 2015/07/29 04:22:35]

Yeah, that's possible and desirable but changing all WebCallbacks makes this CL
(and other CLs in this series) much bigger. After this CL is landed, it will be
possible to fix callbacks module by module, so I'd like to fix them later.

-using WebPushUnsubscribeCallbacks = WebCallbacks<bool*, WebPassOwnPtr<WebPushError>>;
+using WebPushUnsubscribeCallbacks = WebCallbacks<bool, const WebPushError&>;
 
 class WebPushProvider {
 public:
     virtual ~WebPushProvider() { }
 
     // Takes ownership of the WebPushSubscriptionCallbacks.
     // Does not take ownership of the WebServiceWorkerRegistration.
     virtual void subscribe(WebServiceWorkerRegistration*, const WebPushSubscriptionOptions&, WebPushSubscriptionCallbacks*) = 0;
 
     // Takes ownership of the WebPushSubscriptionCallbacks.
     // Does not take ownership of the WebServiceWorkerRegistration.
     virtual void getSubscription(WebServiceWorkerRegistration*, WebPushSubscriptionCallbacks*) = 0;
 
     // Takes ownership of the WebPushPermissionStatusCallbacks.
     // Does not take ownership of the WebServiceWorkerRegistration.
     virtual void getPermissionStatus(WebServiceWorkerRegistration*, const WebPushSubscriptionOptions&, WebPushPermissionStatusCallbacks*) = 0;
 
     // Takes ownership if the WebPushUnsubscribeCallbacks.
     // Does not take ownership of the WebServiceWorkerRegistration.
     virtual void unsubscribe(WebServiceWorkerRegistration*, WebPushUnsubscribeCallbacks*) = 0;
 };
 
 } // namespace blink
 
 #endif // WebPushProvider_h