Change CSSParserContext to either take explicit or implicit referrer

third_party/WebKit/Source/core/css/StyleRuleImport.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * (C) 2002-2003 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2002, 2005, 2006, 2008, 2009, 2010, 2012 Apple Inc. All rights
  * reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 60 matching lines @@
     const CSSStyleSheetResource* cachedStyleSheet) {
   if (m_styleSheet)
     m_styleSheet->clearOwnerRule();
 
   Document* document = nullptr;
   const CSSParserContext* context = strictCSSParserContext();
   if (m_parentStyleSheet) {
     document = m_parentStyleSheet->singleOwnerDocument();
     context = m_parentStyleSheet->parserContext();
   }
-  context = CSSParserContext::create(
-      context, baseURL, charset,
-      (!baseURL.isNull() && document)
-          ? Referrer(baseURL.strippedForUseAsReferrer(),
-                     document->getReferrerPolicy())
-          : context->referrer(),
-      document);
+  context =
+      CSSParserContext::create(context, baseURL,
+                               document ? document->getReferrerPolicy()
+                                        : context->referrer().referrerPolicy,

[estark, 2017/03/28 11:02:34]

This looks like it will result in a different referrer in certain cases; for
example in the case where |m_parentStyleSheet| is null, we would previously end
up with CSSParserContext having referrer ("", ReferrerPolicyDefault), but now
it'll be (|baseURL|, ReferrerPolicyDefault), meaning we'll send non-empty
referrers in cases where we weren't previously. Is that correct and/or
intentional?

[jochen (gone - plz use gerrit), 2017/03/28 11:21:23]

good point.

I think it's correct(er) now. If we have a baseURL (here, the response().url()
from loading the stylesheet), we should use it as referrer (according to my
proposed spec change :) )

+                               charset, document);
 
   m_styleSheet = StyleSheetContents::create(this, href, context);
 
   m_styleSheet->parseAuthorStyleSheet(
       cachedStyleSheet, document ? document->getSecurityOrigin() : 0);
 
   m_loading = false;
 
   if (m_parentStyleSheet) {
     m_parentStyleSheet->notifyLoadedSheet(cachedStyleSheet);
@@ skipping 45 matching lines @@
     // the sheet being imported is pending.
     if (m_parentStyleSheet && m_parentStyleSheet->loadCompleted() &&
         rootSheet == m_parentStyleSheet)
       m_parentStyleSheet->startLoadingDynamicSheet();
     m_loading = true;
     m_resource->addClient(m_styleSheetClient);
   }
 }
 
 }  // namespace blink