Implement support for link type serviceworker in link elements.

third_party/WebKit/Source/core/html/HTMLLinkElement.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Google 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 125 matching lines @@
     static PassRefPtrWillBeRawPtr<HTMLLinkElement> create(Document&, bool createdByParser);
     ~HTMLLinkElement() override;
 
     KURL href() const;
     const AtomicString& rel() const;
     String media() const { return m_media; }
     String typeValue() const { return m_type; }
     String asValue() const { return m_as; }
     const LinkRelAttribute& relAttribute() const { return m_relAttribute; }
     DOMTokenList& relList() const { return static_cast<DOMTokenList&>(*m_relList); }
+    String scope() const { return m_scope; }
 
     const AtomicString& type() const;
 
     IconType getIconType() const;
 
     // the icon sizes as parsed from the HTML attribute
     const Vector<IntSize>& iconSizes() const;
 
     bool async() const;
 
@@ skipping 64 matching lines @@
     OwnPtrWillBeMember<LinkResource> m_link;
     OwnPtrWillBeMember<LinkLoader> m_linkLoader;
 
     String m_type;
     String m_as;
     String m_media;
     RefPtrWillBeMember<DOMTokenList> m_sizes;
     Vector<IntSize> m_iconSizes;
     RawPtrWillBeMember<RelList> m_relList;
     LinkRelAttribute m_relAttribute;
+    String m_scope;
 
     bool m_createdByParser;
     bool m_isInShadowTree;
 };
 
 } // namespace blink
 
 #endif // HTMLLinkElement_h