Fire AX notifications on list box options.

Source/core/html/HTMLOptionElement.cpp

Index: Source/core/html/HTMLOptionElement.cpp
diff --git a/Source/core/html/HTMLOptionElement.cpp b/Source/core/html/HTMLOptionElement.cpp
index f14dd4b81dbb1294fd148c9a5c31737391f81659..97a8e40d73dc7ed852dd906916e95f2aabf6f8ea 100644
--- a/Source/core/html/HTMLOptionElement.cpp
+++ b/Source/core/html/HTMLOptionElement.cpp
@@ -29,6 +29,7 @@
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "core/HTMLNames.h"
+#include "core/dom/AXObjectCache.h"
 #include "core/dom/Document.h"
 #include "core/dom/NodeComputedStyle.h"
 #include "core/dom/NodeTraversal.h"
@@ -264,8 +265,19 @@ void HTMLOptionElement::setSelectedState(bool selected)
     m_isSelected = selected;
     pseudoStateChanged(CSSSelector::PseudoChecked);
 
-    if (HTMLSelectElement* select = ownerSelectElement())
+    if (HTMLSelectElement* select = ownerSelectElement()) {
         select->invalidateSelectedItems();
+
+        if (AXObjectCache* cache = document().existingAXObjectCache()) {
+            // If there is a layoutObject (most common), fire accessibility notifications
+            // only when it's a listbox (and not a menu list). If there's no layoutObject,
+            // fire them anyway just to be safe (to make sure the AX tree is in sync).
+            if (!select->layoutObject() || select->layoutObject()->isListBox()) {
+                cache->listboxOptionStateChanged(this);
+                cache->listboxSelectedChildrenChanged(select);
+            }
+        }
+    }
 }
 
 void HTMLOptionElement::childrenChanged(const ChildrenChange& change)