Implement the inert attribute

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

 /*
  * Copyright (C) 2008, 2009, 2011 Apple Inc. All rights reserved.
  *
  * 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 558 matching lines @@
         if (getNode()->isInert()) {
             if (ignoredReasons) {
                 HTMLDialogElement* dialog = getActiveDialogElement(getNode());
                 if (dialog) {
                     AXObject* dialogObject = axObjectCache().getOrCreate(dialog);
                     if (dialogObject)
                         ignoredReasons->append(IgnoredReason(AXActiveModalDialog, dialogObject));
                     else
                         ignoredReasons->append(IgnoredReason(AXInert));
                 } else {
-                    // TODO(aboxhall): handle inert attribute if it eventuates
-                    ignoredReasons->append(IgnoredReason(AXInert));
+                    const AXObject* inertRootEl = inertRoot();
+                    if (inertRootEl == this)
+                        ignoredReasons->append(IgnoredReason(AXInert));
+                    else
+                        ignoredReasons->append(IgnoredReason(AXInertRoot, inertRootEl));
                 }
             }
             return true;
         }
     } else {
         AXObject* parent = parentObject();
         if (parent && parent->isInertOrAriaHidden()) {
             if (ignoredReasons)
                 parent->computeIsInertOrAriaHidden(ignoredReasons);
             return true;
@@ skipping 35 matching lines @@
 const AXObject* AXObject::ariaHiddenRoot() const
 {
     for (const AXObject* object = this; object; object = object->parentObject()) {
         if (equalIgnoringCase(object->getAttribute(aria_hiddenAttr), "true"))
             return object;
     }
 
     return 0;
 }
 
+const AXObject* AXObject::inertRoot() const
+{
+    for (const AXObject* object = this; object; object = object->parentObject()) {

[dmazzoni, 2016/06/29 17:00:56]

Since "inert" is a property of the DOM, and aria-owns can rearrange the
accessibility tree, this should probably walk the DOM parent chain looking for
"inert", rather than walking the accessibility parent chain.

+        if (object->hasAttribute(inertAttr))
+            return object;
+    }
+
+    return 0;
+}
+
 bool AXObject::isDescendantOfDisabledNode() const
 {
     updateCachedAttributeValuesIfNeeded();
     return m_cachedIsDescendantOfDisabledNode;
 }
 
 const AXObject* AXObject::disabledAncestor() const
 {
     const AtomicString& disabled = getAttribute(aria_disabledAttr);
     if (equalIgnoringCase(disabled, "true"))
@@ skipping 1104 matching lines @@
 
 DEFINE_TRACE(AXObject)
 {
     visitor->trace(m_children);
     visitor->trace(m_parent);
     visitor->trace(m_cachedLiveRegionRoot);
     visitor->trace(m_axObjectCache);
 }
 
 } // namespace blink