Refactor WebRTC certificate generation to use WebPassOwnPtr.

third_party/WebKit/public/platform/WebRTCCertificate.h

 // Copyright 2015 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 WebRTCCertificate_h
 #define WebRTCCertificate_h
 
+#include "public/platform/WebPassOwnPtr.h"
 #include "public/platform/WebRTCKeyParams.h"
 
 namespace blink {
 
 // WebRTCCertificate is an interface defining what Blink needs to know about certificates,
 // hiding Chromium and WebRTC layer implementation details. It is possible to create
 // shallow copies of the WebRTCCertificate. When all copies are destroyed, the
 // implementation specific data must be freed. WebRTCCertificate objects thus act as
 // references to the reference counted internal data.
 class WebRTCCertificate {
 public:
     WebRTCCertificate() = default;
     virtual ~WebRTCCertificate() = default;
 
     // Copies the WebRTCCertificate object without copying the underlying implementation
     // specific (WebRTC layer) certificate. When all copies are destroyed the underlying
     // data is freed.
-    virtual WebRTCCertificate* shallowCopy() const = 0;
+    virtual WebPassOwnPtr<WebRTCCertificate> shallowCopy() const = 0;
 
     virtual const WebRTCKeyParams& keyParams() const = 0;
 
     // Returns the expiration time in ms relative to epoch, 1970-01-01T00:00:00Z.
     virtual uint64_t expires() const = 0;
 
 private:
     WebRTCCertificate(const WebRTCCertificate&) = delete;
     WebRTCCertificate& operator=(const WebRTCCertificate&) = delete;
 };
 
 } // namespace blink
 
 #endif // WebRTCCertificate_h