[selectors4] Implement :focus-within pseudo-class

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 1007 matching lines @@
     SetNeedsStyleRecalc(
         change_type,
         StyleChangeReasonForTracing::CreateWithExtraData(
             StyleChangeReason::kPseudoClass, StyleChangeExtraData::g_focus));
   }
   if (IsElementNode() && ToElement(this)->ChildrenOrSiblingsAffectedByFocus())
     ToElement(this)->PseudoStateChanged(CSSSelector::kPseudoFocus);
 
   LayoutTheme::GetTheme().ControlStateChanged(*GetLayoutObject(),
                                               kFocusControlState);
+  FocusWithinStateChanged();
+}
+
+void ContainerNode::FocusWithinStateChanged() {
+  if (GetComputedStyle() && GetComputedStyle()->AffectedByFocusWithin()) {
+    StyleChangeType change_type =
+        GetComputedStyle()->HasPseudoStyle(kPseudoIdFirstLetter)
+            ? kSubtreeStyleChange
+            : kLocalStyleChange;
+    SetNeedsStyleRecalc(change_type,
+                        StyleChangeReasonForTracing::CreateWithExtraData(
+                            StyleChangeReason::kPseudoClass,
+                            StyleChangeExtraData::g_focus_within));
+  }
+  if (IsElementNode() &&
+      ToElement(this)->ChildrenOrSiblingsAffectedByFocusWithin())
+    ToElement(this)->PseudoStateChanged(CSSSelector::kPseudoFocusWithin);
 }
 
 void ContainerNode::SetFocused(bool received) {
   // Recurse up author shadow trees to mark shadow hosts if it matches :focus.
   // TODO(kochi): Handle UA shadows which marks multiple nodes as focused such
   // as <input type="date"> the same way as author shadow.
   if (ShadowRoot* root = ContainingShadowRoot()) {
     if (root->GetType() != ShadowRootType::kUserAgent)
       OwnerShadowHost()->SetFocused(received);
   }
 
   // If this is an author shadow host and indirectly focused (has focused
   // element within its shadow root), update focus.
   if (IsElementNode() && GetDocument().FocusedElement() &&
       GetDocument().FocusedElement() != this) {
     if (ToElement(this)->AuthorShadowRoot())
       received =
           received && ToElement(this)->AuthorShadowRoot()->delegatesFocus();
   }
 
   if (IsFocused() == received)
     return;
 
   Node::SetFocused(received);
 
   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::SetActive(bool down) {
   if (down == IsActive())
     return;
 
   Node::SetActive(down);
 
   if (!GetLayoutObject()) {
     if (IsElementNode() &&
@@ skipping 408 matching lines @@
     return true;
 
   if (node->IsElementNode() && ToElement(node)->Shadow())
     return true;
 
   return false;
 }
 #endif
 
 }  // namespace blink