Restore adoptNode and importNode to dart:html

tests/html/document_test.dart

 library DocumentTest;
 import '../../pkg/unittest/lib/unittest.dart';
 import '../../pkg/unittest/lib/html_individual_config.dart';
 import 'dart:html';
 
 main() {
   useHtmlIndividualConfiguration();
 
   var isElement = predicate((x) => x is Element, 'is an Element');
   var isDivElement = predicate((x) => x is DivElement, 'is a DivElement');
@@ skipping 43 matching lines @@
       expect(rs, isNotNull);
     });
 
     test('CreateElement', () {
       // FIXME: nifty way crashes, do it boring way.
       expect(new Element.tag('span'), isElement);
       expect(new Element.tag('div'), isDivElement);
       expect(new Element.tag('a'), isAnchorElement);
       expect(new Element.tag('bad_name'), isUnknownElement);
     });
+
+    test('adoptNode', () {
+      var div = new Element.html('<div><div id="foo">bar</div></div>');
+      var doc = document.implementation.createHtmlDocument('');
+      expect(doc.adoptNode(div), div);
+      expect(div.document, doc);
+      doc.body.nodes.add(div);
+      expect(doc.query('#foo').text, 'bar');
+    });
+
+    test('importNode', () {
+      var div = new Element.html('<div><div id="foo">bar</div></div>');
+      var doc = document.implementation.createHtmlDocument('');
+      var div2 = doc.importNode(div, true);
+      expect(div2, isNot(equals(div)));
+      expect(div2.document, doc);
+      doc.body.nodes.add(div2);
+      expect(doc.query('#foo').text, 'bar');
+    });
   });
 }