Make Range methods to work with detached node

LayoutTests/fast/dom/Range/surroundContents-for-detached-node.html

+<div id="container">
+<p id="description"></p>
+<div id="sample">0123456789</div>
+</div>
+<div id="console"></div>
+<script src="../../js/resources/js-test-pre.js"></script>
+<script>
+description('Range.surroundContents() should not throw exception for detached node.');
+function $(id) { return document.getElementById(id); }
+
+function surroundContents(node) {
+    var range = document.createRange();
+    range.setStart(node.firstChild, 2);
+    range.setEnd(node.firstChild, 6);
+    var newNode = document.createElement('b');
+    range.surroundContents(newNode);
+    return newNode.outerHTML;
+}
+
+var sample = $('sample');
+var expected = '<b>' + sample.firstChild.textContent.substring(2, 6) + '</b>';
+shouldBeEqualToString('surroundContents(sample.cloneNode(true))', expected);
+sample.parentNode.removeChild(sample);
+shouldBeEqualToString('surroundContents(sample)', expected);
+
+if (window.testRunner)
+    $('container').outerHTML = '';
+</script>
+<script src="../../js/resources/js-test-post.js"></script>