Fix focus navigation for nested slot case

third_party/WebKit/Source/core/page/FocusController.cpp

 /*
  * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nuanti Ltd.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 53 matching lines @@
 
 using namespace HTMLNames;
 
 namespace {
 
 inline bool isShadowInsertionPointFocusScopeOwner(Element& element) {
   return isActiveShadowInsertionPoint(element) &&
          toHTMLShadowElement(element).olderShadowRoot();
 }
 
+inline bool hasCustomFocusLogic(const Element& element) {
+  return element.isHTMLElement() &&
+         toHTMLElement(element).hasCustomFocusLogic();
+}
+
+inline bool isShadowHostWithoutCustomFocusLogic(const Element& element) {
+  return isShadowHost(element) && !hasCustomFocusLogic(element);
+}
+
+inline bool isNonKeyboardFocusableShadowHost(const Element& element) {
+  return isShadowHostWithoutCustomFocusLogic(element) &&
+         !(element.shadowRootIfV1() ? element.isFocusable()
+                                    : element.isKeyboardFocusable());
+}
+
+inline bool isKeyboardFocusableShadowHost(const Element& element) {
+  return isShadowHostWithoutCustomFocusLogic(element) &&
+         element.isKeyboardFocusable();
+}
+
+inline bool isNonFocusableFocusScopeOwner(Element& element) {
+  return isNonKeyboardFocusableShadowHost(element) ||
+         isShadowInsertionPointFocusScopeOwner(element) ||
+         isHTMLSlotElement(element);
+}
+
+inline bool isShadowHostDelegatesFocus(const Element& element) {
+  return element.authorShadowRoot() &&
+         element.authorShadowRoot()->delegatesFocus();
+}
+
 class ScopedFocusNavigation {
   STACK_ALLOCATED();
 
  public:
   Element* currentElement() const;
   void setCurrentElement(Element*);
   void moveToNext();
   void moveToPrevious();
   void moveToFirst();
   void moveToLast();
@@ skipping 112 matching lines @@
     m_current = first;
   }
 }
 
 void ScopedFocusNavigation::moveToLast() {
   if (m_rootSlot) {
     if (!m_slotFallbackTraversal) {
       HeapVector<Member<Node>> assignedNodes = m_rootSlot->assignedNodes();
       for (auto assignedNode = assignedNodes.rbegin();
            assignedNode != assignedNodes.rend(); ++assignedNode) {
-        if ((*assignedNode)->isElementNode()) {
-          m_current =
-              ElementTraversal::lastWithinOrSelf(*toElement(*assignedNode));
-          break;
+        if (!(*assignedNode)->isElementNode())
+          continue;
+
+        Element* last = ElementTraversal::lastWithin(*toElement(*assignedNode));
+        if (!last) {
+          m_current = toElement(*assignedNode);
+        } else {
+          while (last) {
+            Element* ancestor =
+                SlotScopedTraversal::nearestAncestorAssignedToSlot(*last);
+            DCHECK(ancestor);
+            if (ancestor == *assignedNode)
+              break;
+            last = ancestor->parentElement();
+          }
+          DCHECK(last);
+          m_current = last;
         }
+        break;
       }
     } else {
       Element* last = ElementTraversal::lastWithin(*m_rootSlot);
       while (last &&
              !ScopedFocusNavigation::isSlotFallbackScopedForThisSlot(
                  *m_rootSlot, *last))
         last = ElementTraversal::previous(*last, m_rootSlot);
       m_current = last;
     }
   } else {
@@ skipping 152 matching lines @@
   if (LocalDOMWindow* window = document->domWindow())
     window->dispatchEvent(
         Event::create(focused ? EventTypeNames::focus : EventTypeNames::blur));
   if (focused && document->focusedElement()) {
     Element* focusedElement(document->focusedElement());
     focusedElement->setFocused(true);
     dispatchFocusEvent(*document, *focusedElement);
   }
 }
 
-inline bool hasCustomFocusLogic(const Element& element) {
-  return element.isHTMLElement() &&
-         toHTMLElement(element).hasCustomFocusLogic();
-}
-
-inline bool isShadowHostWithoutCustomFocusLogic(const Element& element) {
-  return isShadowHost(element) && !hasCustomFocusLogic(element);
-}
-
-inline bool isNonKeyboardFocusableShadowHost(const Element& element) {
-  return isShadowHostWithoutCustomFocusLogic(element) &&
-         !(element.shadowRootIfV1() ? element.isFocusable()
-                                    : element.isKeyboardFocusable());
-}
-
-inline bool isKeyboardFocusableShadowHost(const Element& element) {
-  return isShadowHostWithoutCustomFocusLogic(element) &&
-         element.isKeyboardFocusable();
-}
-
-inline bool isNonFocusableFocusScopeOwner(Element& element) {
-  return isNonKeyboardFocusableShadowHost(element) ||
-         isShadowInsertionPointFocusScopeOwner(element) ||
-         isHTMLSlotElement(element);
-}
-
-inline bool isShadowHostDelegatesFocus(const Element& element) {
-  return element.authorShadowRoot() &&
-         element.authorShadowRoot()->delegatesFocus();
-}
-
 inline int adjustedTabIndex(Element& element) {
   return (isNonKeyboardFocusableShadowHost(element) ||
           isShadowInsertionPointFocusScopeOwner(element))
              ? 0
              : element.tabIndex();
 }
 
 inline bool shouldVisit(Element& element) {
   return element.isKeyboardFocusable() ||
          isNonFocusableFocusScopeOwner(element);
@@ skipping 1001 matching lines @@
 
   return consumed;
 }
 
 DEFINE_TRACE(FocusController) {
   visitor->trace(m_page);
   visitor->trace(m_focusedFrame);
 }
 
 }  // namespace blink