Implement computedRole and computedName (behind a flag)

Source/core/dom/Document.cpp

Index: Source/core/dom/Document.cpp
diff --git a/Source/core/dom/Document.cpp b/Source/core/dom/Document.cpp
index 680e990808b3fdfbbd0959929a10c92dd533902a..fff6cd2170f51a52c3cab06540911399a02e1cbb 100644
--- a/Source/core/dom/Document.cpp
+++ b/Source/core/dom/Document.cpp
@@ -2261,7 +2261,11 @@ AXObjectCache* Document::axObjectCache() const
     Settings* settings = this->settings();
     if (!settings || !settings->accessibilityEnabled())
         return 0;
+    return alwaysCreateAxObjectCache();
+}
 
+AXObjectCache* Document::alwaysCreateAxObjectCache() const
+{
     // The only document that actually has a AXObjectCache is the top-level
     // document.  This is because we need to be able to get from any WebCoreAXObject
     // to any other WebCoreAXObject on the same page.  Using a single cache allows