Replace elementHasLegalLinkAttribute() helper with virtual function

Source/core/dom/Element.cpp

Index: Source/core/dom/Element.cpp
diff --git a/Source/core/dom/Element.cpp b/Source/core/dom/Element.cpp
index 1b88ddbf87c87a51d523e8985ea2cfadeba4c3c7..e3833d12c9a809d70f202098ae5dad23d485916f 100644
--- a/Source/core/dom/Element.cpp
+++ b/Source/core/dom/Element.cpp
@@ -1050,6 +1050,11 @@ void Element::attributeChanged(const QualifiedName& name, const AtomicString& ne
         cache->handleAttributeChanged(name, this);
 }
 
+bool Element::hasLegalLinkAttribute(const QualifiedName&) const
+{
+    return false;
+}
+
 inline void Element::attributeChangedFromParserOrByCloning(const QualifiedName& name, const AtomicString& newValue, AttributeModificationReason reason)
 {
     if (name == isAttr)