Add handling to respect role attribute in AXObjects.

Source/modules/accessibility/AXSlider.cpp

 /*
  * Copyright (C) 2009 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 31 matching lines @@
 AXSlider::AXSlider(LayoutObject* layoutObject, AXObjectCacheImpl* axObjectCache)
     : AXLayoutObject(layoutObject, axObjectCache)
 {
 }
 
 PassRefPtr<AXSlider> AXSlider::create(LayoutObject* layoutObject, AXObjectCacheImpl* axObjectCache)
 {
     return adoptRef(new AXSlider(layoutObject, axObjectCache));
 }
 
+AccessibilityRole AXSlider::roleValue() const
+{
+    AccessibilityRole ariaRole = ariaRoleAttribute();
+    if (ariaRole != UnknownRole)
+        return ariaRole;
+    return SliderRole;
+}
+
 AccessibilityOrientation AXSlider::orientation() const
 {
     // Default to horizontal in the unknown case.
     if (!m_layoutObject)
         return AccessibilityOrientationHorizontal;
 
     LayoutStyle* style = m_layoutObject->style();
     if (!style)
         return AccessibilityOrientationHorizontal;
 
@@ skipping 88 matching lines @@
         return LayoutRect();
     return toElement(sliderLayoutObject->node())->closedShadowRoot()->getElementById(ShadowElementNames::sliderThumb())->boundingBox();
 }
 
 bool AXSliderThumb::computeAccessibilityIsIgnored() const
 {
     return accessibilityIsIgnoredByDefault();
 }
 
 } // namespace blink