Make generateReferrerHeader() return a Referrer instead of a String

Source/core/frame/RemoteFrame.cpp

 // 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.
 
 #include "config.h"
 #include "core/frame/RemoteFrame.h"
 
 #include "core/frame/RemoteFrameClient.h"
 #include "core/frame/RemoteFrameView.h"
 #include "core/html/HTMLFrameOwnerElement.h"
@@ skipping 14 matching lines @@
 RemoteFrame::~RemoteFrame()
 {
     setView(nullptr);
 }
 
 void RemoteFrame::navigate(Document& originDocument, const KURL& url, bool lockBackForwardList)
 {
     // The process where this frame actually lives won't have sufficient information to determine
     // correct referrer, since it won't have access to the originDocument. Set it now.
     ResourceRequest request(url);
-    Referrer referrer(SecurityPolicy::generateReferrerHeader(originDocument.referrerPolicy(), url, originDocument.outgoingReferrer()), originDocument.referrerPolicy());
-    request.setHTTPReferrer(referrer);
+    request.setHTTPReferrer(SecurityPolicy::generateReferrerHeader(originDocument.referrerPolicy(), url, originDocument.outgoingReferrer()));
     remoteFrameClient()->navigate(request, lockBackForwardList);
 }
 
 void RemoteFrame::detach()
 {
     detachChildren();
     m_host = nullptr;
 }
 
 void RemoteFrame::trace(Visitor* visitor)
@@ skipping 20 matching lines @@
         owner->setWidget(view);
     }
 }
 
 RemoteFrameClient* RemoteFrame::remoteFrameClient() const
 {
     return static_cast<RemoteFrameClient*>(client());
 }
 
 } // namespace blink