nsDOMImplementation::HasFeature(const nsString& aFeature, const nsString& aVersion,
nsDOMImplementation::HasFeature(const nsAReadableString& aFeature, const nsAReadableString& aVersion,
nsDOMImplementation::HasFeature(const nsString& aFeature,                                 const nsString& aVersion,                                 PRBool* aReturn){  return nsGenericElement::InternalSupports(aFeature, aVersion, aReturn);}