rv = UnsetAttr(kNameSpaceID_HTML, nsHTMLAtoms::checked, PR_TRUE);
rv = UnsetAttr(kNameSpaceID_None, nsHTMLAtoms::checked, PR_TRUE);
nsHTMLInputElement::SetDefaultChecked(PRBool aDefaultChecked){  nsresult rv;  if (aDefaultChecked) {    rv = SetAttr(kNameSpaceID_HTML, nsHTMLAtoms::checked,                 NS_LITERAL_STRING(""), PR_TRUE);  } else {    rv = UnsetAttr(kNameSpaceID_HTML, nsHTMLAtoms::checked, PR_TRUE);  }    return rv;}