Implement ShadowRoot.delegatesFocus 1/4 (focus navigation)

Source/core/dom/shadow/ShadowRoot.h

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 106 matching lines @@
     ShadowRoot* olderShadowRoot() const { return next(); }
 
     String innerHTML() const;
     void setInnerHTML(const String&, ExceptionState&);
 
     PassRefPtrWillBeRawPtr<Node> cloneNode(bool, ExceptionState&);
     PassRefPtrWillBeRawPtr<Node> cloneNode(ExceptionState& exceptionState) { return cloneNode(true, exceptionState); }
 
     StyleSheetList* styleSheets();
 
+    void setDelegatesFocus(bool flag) { m_delegatesFocus = flag; }
+    bool delegatesFocus() const { return m_delegatesFocus; }
+
     DECLARE_VIRTUAL_TRACE();
 
 private:
     ShadowRoot(Document&, ShadowRootType);
     virtual ~ShadowRoot();
 
 #if !ENABLE(OILPAN)
     virtual void dispose() override;
 #endif
 
@@ skipping 11 matching lines @@
     // FIXME: This shouldn't happen. https://bugs.webkit.org/show_bug.cgi?id=88834
     bool isOrphan() const { return !host(); }
 
     RawPtrWillBeMember<ShadowRoot> m_prev;
     RawPtrWillBeMember<ShadowRoot> m_next;
     OwnPtrWillBeMember<ShadowRootRareData> m_shadowRootRareData;
     unsigned m_numberOfStyles : 27;
     unsigned m_type : 1;
     unsigned m_registeredWithParentShadowRoot : 1;
     unsigned m_descendantInsertionPointsIsValid : 1;
+    unsigned m_delegatesFocus : 1;
 };
 
 inline Element* ShadowRoot::activeElement() const
 {
     return adjustedFocusedElement();
 }
 
 DEFINE_NODE_TYPE_CASTS(ShadowRoot, isShadowRoot());
 DEFINE_TYPE_CASTS(ShadowRoot, TreeScope, treeScope, treeScope->rootNode().isShadowRoot(), treeScope.rootNode().isShadowRoot());
 DEFINE_TYPE_CASTS(TreeScope, ShadowRoot, shadowRoot, true, true);
 
 } // namespace blink
 
 #endif // ShadowRoot_h