Uses the activedescendant_changed event received from Blink to fire the right focus event

third_party/WebKit/Source/modules/accessibility/AXListBox.cpp

Index: third_party/WebKit/Source/modules/accessibility/AXListBox.cpp
diff --git a/third_party/WebKit/Source/modules/accessibility/AXListBox.cpp b/third_party/WebKit/Source/modules/accessibility/AXListBox.cpp
index 0d04e157dc1f8063e67b47eab36176414e71c943..833bd75490569161cbfd5c6a9528284630e32864 100644
--- a/third_party/WebKit/Source/modules/accessibility/AXListBox.cpp
+++ b/third_party/WebKit/Source/modules/accessibility/AXListBox.cpp
@@ -62,7 +62,7 @@ AccessibilityRole AXListBox::determineAccessibilityRole()
     return ListBoxRole;
 }
 
-AXObject* AXListBox::activeDescendant() const
+AXObject* AXListBox::activeDescendant()
 {
     if (!isHTMLSelectElement(getNode()))
         return nullptr;
@@ -91,12 +91,7 @@ void AXListBox::activeIndexChanged()
     if (!select->focused())
         return;
 
-    if (m_activeIndex >= 0 && m_activeIndex < static_cast<int>(select->length())) {
-        HTMLOptionElement* option = select->item(m_activeIndex);
-        axObjectCache().postNotification(option, AXObjectCacheImpl::AXFocusedUIElementChanged);
-    } else {
-        axObjectCache().postNotification(this, AXObjectCacheImpl::AXFocusedUIElementChanged);
-    }
+    axObjectCache().postNotification(this, AXObjectCacheImpl::AXActiveDescendantChanged);
 }
 
 } // namespace blink