Implement aria-modal

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

Index: third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp
diff --git a/third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp b/third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp
index eb78cb10a5099650fd185e81be9c8c5553912d57..0aef97762c39958dba8bec31e74e345339f66cbf 100644
--- a/third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp
+++ b/third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp
@@ -1152,6 +1152,24 @@ AccessibilityExpanded AXNodeObject::isExpanded() const {
   return ExpandedUndefined;
 }
 
+bool AXNodeObject::isModal() const {
+  if (roleValue() != DialogRole && roleValue() != AlertDialogRole)
+    return false;
+
+  if (hasAttribute(aria_modalAttr)) {
+    const AtomicString& modal = getAttribute(aria_modalAttr);
+    if (equalIgnoringCase(modal, "true"))
+      return true;
+    if (equalIgnoringCase(modal, "false"))
+      return false;
+  }
+
+  if (getNode() && isHTMLDialogElement(*getNode()))
+    return toElement(getNode())->isInTopLayer();
+
+  return false;
+}
+
 bool AXNodeObject::isPressed() const {
   if (!isButton())
     return false;