Add handling to respect role attribute in AXObjects.

Source/modules/accessibility/AXSlider.h

 /*
  * 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 32 matching lines @@
     static PassRefPtr<AXSlider> create(LayoutObject*, AXObjectCacheImpl*);
     virtual ~AXSlider() { }
 
 protected:
     AXSlider(LayoutObject*, AXObjectCacheImpl*);
 
 private:
     HTMLInputElement* element() const;
     virtual AXObject* elementAccessibilityHitTest(const IntPoint&) const override final;
 
-    virtual AccessibilityRole roleValue() const override { return SliderRole; }
+    virtual AccessibilityRole roleValue() const override;
     virtual bool isSlider() const override final { return true; }
     virtual bool isControl() const override final { return true; }
 
     virtual void addChildren() override final;
 
     virtual bool canSetValueAttribute() const override final { return true; }
     const AtomicString& getAttribute(const QualifiedName& attribute) const;
 
     virtual void setValue(const String&) override final;
     virtual AccessibilityOrientation orientation() const override final;
@@ skipping 12 matching lines @@
 private:
     explicit AXSliderThumb(AXObjectCacheImpl*);
 
     virtual bool computeAccessibilityIsIgnored() const override;
 };
 
 
 } // namespace blink
 
 #endif // AXSlider_h