Re-land: Don't keep recreating AXMenuListPopup

Source/modules/accessibility/AXObjectCacheImpl.cpp

Index: Source/modules/accessibility/AXObjectCacheImpl.cpp
diff --git a/Source/modules/accessibility/AXObjectCacheImpl.cpp b/Source/modules/accessibility/AXObjectCacheImpl.cpp
index ecdc664789c58f5d518502ac01511449010b577b..8bce3f7a8d4173982977190f9302a766a6914f78 100644
--- a/Source/modules/accessibility/AXObjectCacheImpl.cpp
+++ b/Source/modules/accessibility/AXObjectCacheImpl.cpp
@@ -203,6 +203,21 @@ AXObject* AXObjectCacheImpl::get(LayoutObject* layoutObject)
     return m_objects.get(axID);
 }
 
+// Returns true if |node| is an <option> element and its parent <select>
+// is a menu list (not a list box).
+static bool isMenuListOption(Node* node)
+{
+    if (!isHTMLOptionElement(node))
+        return false;
+    Element* parent = node->parentElement();
+    if (isHTMLOptGroupElement(parent))
+        parent = parent->parentElement();
+    if (!isHTMLSelectElement(parent))
+        return false;
+    LayoutObject* layoutObject = toHTMLSelectElement(parent)->layoutObject();
+    return layoutObject && layoutObject->isMenuList();
+}
+
 AXObject* AXObjectCacheImpl::get(Node* node)
 {
     if (!node)
@@ -214,7 +229,7 @@ AXObject* AXObjectCacheImpl::get(Node* node)
     AXID nodeID = m_nodeObjectMapping.get(node);
     ASSERT(!HashTraits<AXID>::isDeletedValue(nodeID));
 
-    if (node->layoutObject() && nodeID && !layoutID) {
+    if (node->layoutObject() && nodeID && !layoutID && !isMenuListOption(node)) {
         // This can happen if an AXNodeObject is created for a node that's not
         // laid out, but later something changes and it gets a layoutObject (like if it's
         // reparented).
@@ -312,6 +327,9 @@ PassRefPtr<AXObject> AXObjectCacheImpl::createFromRenderer(LayoutObject* layoutO
 
 PassRefPtr<AXObject> AXObjectCacheImpl::createFromNode(Node* node)
 {
+    if (isMenuListOption(node))
+        return AXMenuListOption::create(toHTMLOptionElement(node), this);
+
     return AXNodeObject::create(node, this);
 }
 
@@ -368,7 +386,7 @@ AXObject* AXObjectCacheImpl::getOrCreate(Node* node)
     // Or if it's a hidden element, but we still want to expose it because of other ARIA attributes.
     bool inCanvasSubtree = node->parentElement()->isInCanvasSubtree();
     bool isHidden = !node->layoutObject() && isNodeAriaVisible(node);
-    if (!inCanvasSubtree && !isHidden)
+    if (!inCanvasSubtree && !isHidden && !isMenuListOption(node))
         return 0;
 
     RefPtr<AXObject> newObj = createFromNode(node);
@@ -461,9 +479,6 @@ AXObject* AXObjectCacheImpl::getOrCreate(AccessibilityRole role)
     case MenuListPopupRole:
         obj = AXMenuListPopup::create(this);
         break;
-    case MenuListOptionRole:
-        obj = AXMenuListOption::create(this);
-        break;
     case SpinButtonRole:
         obj = AXSpinButton::create(this);
         break;