[import] The first <link rel=import> should win in the cascading order computation.

Source/core/dom/DocumentStyleSheetCollector.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
@@ skipping 15 matching lines @@
 
 #include "config.h"
 #include "core/dom/DocumentStyleSheetCollector.h"
 
 #include "core/css/CSSStyleSheet.h"
 #include "core/css/StyleSheet.h"
 #include "core/dom/DocumentStyleSheetCollection.h"
 
 namespace WebCore {
 
-DocumentStyleSheetCollector::DocumentStyleSheetCollector(Vector<RefPtr<StyleSheet> >& sheetsForList, Vector<RefPtr<CSSStyleSheet> >& activeList)
+DocumentStyleSheetCollector::DocumentStyleSheetCollector(Vector<RefPtr<StyleSheet> >& sheetsForList, Vector<RefPtr<CSSStyleSheet> >& activeList, HashSet<Document*>& visitedDocuments)
     : m_styleSheetsForStyleSheetList(sheetsForList)
     , m_activeAuthorStyleSheets(activeList)
+    , m_visitedDocuments(visitedDocuments)
 {
 }
 
 DocumentStyleSheetCollector::~DocumentStyleSheetCollector()
 {
 }
 
 void DocumentStyleSheetCollector::appendActiveStyleSheets(const Vector<RefPtr<CSSStyleSheet> >& sheets)
 {
     m_activeAuthorStyleSheets.appendVector(sheets);
 }
 
 void DocumentStyleSheetCollector::appendActiveStyleSheet(CSSStyleSheet* sheet)
 {
     m_activeAuthorStyleSheets.append(sheet);
 }
 
 void DocumentStyleSheetCollector::appendSheetForList(StyleSheet* sheet)
 {
     m_styleSheetsForStyleSheetList.append(sheet);
 }
 
 ActiveDocumentStyleSheetCollector::ActiveDocumentStyleSheetCollector(StyleSheetCollection& collection)
-    : DocumentStyleSheetCollector(collection.m_styleSheetsForStyleSheetList, collection.m_activeAuthorStyleSheets)
+    : DocumentStyleSheetCollector(collection.m_styleSheetsForStyleSheetList, collection.m_activeAuthorStyleSheets, m_visitedDocuments)
 {
 }
 
 ImportedDocumentStyleSheetCollector::ImportedDocumentStyleSheetCollector(DocumentStyleSheetCollector& collector, Vector<RefPtr<StyleSheet> >& sheetForList)
-    : DocumentStyleSheetCollector(sheetForList, collector.m_activeAuthorStyleSheets)
+    : DocumentStyleSheetCollector(sheetForList, collector.m_activeAuthorStyleSheets, collector.m_visitedDocuments)
 {
 }
 
 }