Cleanup queryAll to return List<Element>.

tests/html/queryall_test.dart

+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file
+
+#library('NodeListTest');
+#import('../../lib/unittest/unittest.dart');
+#import('../../lib/unittest/html_config.dart');
+#import('dart:html');
+
+main() {
+  useHtmlConfiguration();
+
+  var div = new DivElement();
+  div.id = 'test';
+  document.body.nodes.add(div);
+
+  div.nodes.addAll([
+      new DivElement(),
+      new CanvasElement(),
+      new DivElement(),
+      new Text('Hello'),
+      new DivElement(),
+      new Text('World'),
+      new CanvasElement()]);
+
+  test('queryAll', () {
+      List<Node> all = queryAll('*');
+      for (var e in all) {
+        expect(e is Element, isTrue);
+      }
+    });
+
+  test('document.queryAll', () {
+      List<Element> all1 = queryAll('*');
+      List<Element> all2 = document.queryAll('*');
+      expect(all1.length, equals(all2.length));
+      for (var i = 0; i < all1.length; ++i) {
+        expect(all1[i], equals(all2[i]));
+      }
+    });
+
+  test('queryAll-canvas', () {
+      List<CanvasElement> all = queryAll('canvas');
+      for (var e in all) {
+        expect(e is CanvasElement, isTrue);
+      }
+      expect(all.length, equals(2));
+    });
+
+  test('queryAll-filter', () {
+      List<Element> all = queryAll('*');
+      List<CanvasElement> canvases = all.filter((e) => e is CanvasElement);
+      for (var e in canvases) {
+        expect(e is CanvasElement, isTrue);
+      }
+      expect(canvases.length, equals(2));
+    });
+
+  test('node.queryAll', () {
+      List<Element> list = div.queryAll('*');
+      expect(list.length, equals(5));
+      expect(list[0] is DivElement, isTrue);
+      expect(list[1] is CanvasElement, isTrue);
+      expect(list[2] is DivElement, isTrue);
+      expect(list[3] is DivElement, isTrue);
+      expect(list[4] is CanvasElement, isTrue);
+    });
+
+  test('immutable', () {
+      List<Element> list = div.queryAll('*');
+      int len = list.length;
+      expect(() { list.add(new DivElement()); }, throwsException);
+      expect(list.length, equals(len));
+    });
+}