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

Source/modules/push_messaging/PushError.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 PushError_h
 #define PushError_h
 
 #include "core/dom/DOMException.h"
 #include "platform/heap/Handle.h"
 #include "public/platform/modules/push_messaging/WebPushError.h"
-#include "wtf/OwnPtr.h"
-#include "wtf/PassOwnPtr.h"
 
 namespace blink {
 
 class ScriptPromiseResolver;
 
 class PushError {
     WTF_MAKE_NONCOPYABLE(PushError);
 public:
     // For CallbackPromiseAdapter.
-    using WebType = OwnPtr<WebPushError>;
-    static DOMException* take(ScriptPromiseResolver*, PassOwnPtr<WebPushError> webError);
+    using WebType = const WebPushError&;
+    static DOMException* take(ScriptPromiseResolver*, const WebPushError& webError);
 
 private:
     PushError() = delete;
 };
 
 } // namespace blink
 
 #endif // PushError_h