;
          assert_throws_dom("SecurityError", () => iframe.contentWindow.frameElement);
          assert_throws_dom("SecurityError", function() { iframe.contentWindow.location.origin; });
          assert_throws_dom("SecurityError", function() { iframe.contentWindow.location.href; });
          assert_throws_dom("SecurityError", function() { iframe.contentWindow.location.protocol; });
          assert_throws_dom("SecurityError", function() { iframe.contentWindow.location.host; });
          assert_throws_d