[selectors4] Implement :focus-within pseudo-class

third_party/WebKit/Source/core/dom/Node.h

Index: third_party/WebKit/Source/core/dom/Node.h
diff --git a/third_party/WebKit/Source/core/dom/Node.h b/third_party/WebKit/Source/core/dom/Node.h
index ff4263d878e7e7df2fbe1476a03916a3f3cf6788..d16ec94f89792f3e71175961ccff6482eb38123d 100644
--- a/third_party/WebKit/Source/core/dom/Node.h
+++ b/third_party/WebKit/Source/core/dom/Node.h
@@ -390,6 +390,9 @@ class CORE_EXPORT Node : public EventTarget {
   bool IsFocused() const {
     return IsUserActionElement() && IsUserActionElementFocused();
   }
+  bool HasFocusWithin() const {
+    return IsUserActionElement() && IsUserActionElementHasFocusWithin();
+  }
 
   bool NeedsAttach() const {
     return GetStyleChangeType() == kNeedsReattachStyleChange;
@@ -477,6 +480,7 @@ class CORE_EXPORT Node : public EventTarget {
   }
 
   virtual void SetFocused(bool flag);
+  virtual void SetHasFocusWithin(bool flag);
   virtual void SetActive(bool flag = true);
   virtual void SetDragged(bool flag);
   virtual void SetHovered(bool flag = true);
@@ -902,6 +906,7 @@ class CORE_EXPORT Node : public EventTarget {
   bool IsUserActionElementDragged() const;
   bool IsUserActionElementHovered() const;
   bool IsUserActionElementFocused() const;
+  bool IsUserActionElementHasFocusWithin() const;
 
   void RecalcDistribution();