Revert of Add AX role ,'AXDescriptionList', for dl element.

Source/core/accessibility/AXList.cpp

Index: Source/core/accessibility/AXList.cpp
diff --git a/Source/core/accessibility/AXList.cpp b/Source/core/accessibility/AXList.cpp
index 042c0c5ea511eb0753f766bc8dbbc54116582837..2f316edcd31842645a700befe7c4a33174798ffc 100644
--- a/Source/core/accessibility/AXList.cpp
+++ b/Source/core/accessibility/AXList.cpp
@@ -56,20 +56,4 @@
     return accessibilityIsIgnoredByDefault();
 }
 
-bool AXList::isDescriptionList() const
-{
-    if (!m_renderer)
-        return false;
-
-    Node* node = m_renderer->node();
-    return node && node->hasTagName(dlTag);
-}
-
-AccessibilityRole AXList::roleValue() const
-{
-    if (isDescriptionList())
-        return DescriptionListRole;
-
-    return ListRole;
-}
 } // namespace blink