[selectors4] Use common ancestor strategy for :focus-within

third_party/WebKit/Source/core/dom/ContainerNode.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2013 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
@@ skipping 1051 matching lines @@
           received && ToElement(this)->AuthorShadowRoot()->delegatesFocus();
   }
 
   if (IsFocused() == received)
     return;
 
   Node::SetFocused(received, focus_type);
 
   FocusStateChanged();
 
-  UpdateDistribution();
-  for (ContainerNode* node = this; node;
-       node = FlatTreeTraversal::Parent(*node)) {
-    node->SetHasFocusWithin(received);
-    node->FocusWithinStateChanged();
-  }
-
   if (GetLayoutObject() || received)
     return;
 
   // If :focus sets display: none, we lose focus but still need to recalc our
   // style.
   if (IsElementNode() && ToElement(this)->ChildrenOrSiblingsAffectedByFocus())
     ToElement(this)->PseudoStateChanged(CSSSelector::kPseudoFocus);
   else
     SetNeedsStyleRecalc(
         kLocalStyleChange,
         StyleChangeReasonForTracing::CreateWithExtraData(
             StyleChangeReason::kPseudoClass, StyleChangeExtraData::g_focus));
 
   if (IsElementNode() &&
       ToElement(this)->ChildrenOrSiblingsAffectedByFocusWithin()) {
     ToElement(this)->PseudoStateChanged(CSSSelector::kPseudoFocusWithin);
   } else {
     SetNeedsStyleRecalc(kLocalStyleChange,
                         StyleChangeReasonForTracing::CreateWithExtraData(
                             StyleChangeReason::kPseudoClass,
                             StyleChangeExtraData::g_focus_within));
   }
 }
 
+void ContainerNode::SetHasFocusWithinUpToAncestor(bool flag, Node* ancestor) {
+  for (ContainerNode* node = this; node && node != ancestor;
+       node = FlatTreeTraversal::Parent(*node)) {
+    node->SetHasFocusWithin(flag);
+    node->FocusWithinStateChanged();
+  }
+}
+
 void ContainerNode::SetActive(bool down) {
   if (down == IsActive())
     return;
 
   Node::SetActive(down);
 
   if (!GetLayoutObject()) {
     if (IsElementNode() &&
         ToElement(this)->ChildrenOrSiblingsAffectedByActive())
       ToElement(this)->PseudoStateChanged(CSSSelector::kPseudoActive);
@@ skipping 406 matching lines @@
     return true;
 
   if (node->IsElementNode() && ToElement(node)->Shadow())
     return true;
 
   return false;
 }
 #endif
 
 }  // namespace blink