Introduce new API orientation() to expose aria-orientation correctly.

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 319 matching lines @@
         m_lastKnownIsIgnoredValue = accessibilityIsIgnored() ? IgnoreObject : IncludeObject;
 
     return m_lastKnownIsIgnoredValue == IgnoreObject;
 }
 
 void AXObject::setLastKnownIsIgnoredValue(bool isIgnored)
 {
     m_lastKnownIsIgnoredValue = isIgnored ? IgnoreObject : IncludeObject;
 }
 
-// Lacking concrete evidence of orientation, horizontal means width > height. vertical is height > width;
+// In ARIA 1.1, the default value for aria-orientation changed from horizontal to undefined.
 AccessibilityOrientation AXObject::orientation() const
 {
-    LayoutRect bounds = elementRect();
-    if (bounds.size().width() > bounds.size().height())
-        return AccessibilityOrientationHorizontal;
-    if (bounds.size().height() > bounds.size().width())
-        return AccessibilityOrientationVertical;
-
-    // A tie goes to horizontal.
-    return AccessibilityOrientationHorizontal;
+    return AccessibilityOrientationUndefined;
 }
 
 static String queryString(WebLocalizedString::Name name)
 {
     return Locale::defaultLocale().queryString(name);
 }
 
 String AXObject::actionVerb() const
 {
     // FIXME: Need to add verbs for select elements.
@@ skipping 618 matching lines @@
         return ToggleButtonRole;
     if (ariaHasPopup())
         return PopUpButtonRole;
     // We don't contemplate RadioButtonRole, as it depends on the input
     // type.
 
     return ButtonRole;
 }
 
 } // namespace blink