Implement computedRole and computedName (behind a flag)

Source/core/dom/Element.idl

Index: Source/core/dom/Element.idl
diff --git a/Source/core/dom/Element.idl b/Source/core/dom/Element.idl
index 1e5555ac176ac3ff133929342417ce1fed7109f5..a1fa1ba54e8bb712efb68e710397e93ec5c6fc92 100644
--- a/Source/core/dom/Element.idl
+++ b/Source/core/dom/Element.idl
@@ -117,6 +117,10 @@ interface Element : Node {
 
     [MeasureAs=ElementRequestPointerLock] void requestPointerLock();
 
+    // Experimental accessibility API
+    [RuntimeEnabled=ComputedAccessibilityInfo] readonly attribute DOMString? computedRole;
+    [RuntimeEnabled=ComputedAccessibilityInfo] readonly attribute DOMString? computedName;
+
     // Event handler attributes
     attribute EventHandler onbeforecopy;
     attribute EventHandler onbeforecut;