Changes to make it easier to add elements.

sdk/lib/html/templates/html/impl/impl_DocumentFragment.darttemplate

 // Copyright (c) 2011, 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.
 
 part of html;
 
 Future<CSSStyleDeclaration> _emptyStyleFuture() {
   return _createMeasurementFuture(() => new Element.tag('div').style,
                                   new Completer<CSSStyleDeclaration>());
 }
@@ skipping 92 matching lines @@
     => this._insertAdjacentNode(where, element);
 
   void insertAdjacentText(String where, String text) {
     this._insertAdjacentNode(where, new Text(text));
   }
 
   void insertAdjacentHTML(String where, String text) {
     this._insertAdjacentNode(where, new DocumentFragment.html(text));
   }
 
-  void addText(String text) {
+  void append(Element element) {
+    this.children.add(element);
+  }
+
+  void appendText(String text) {
     this.insertAdjacentText('beforeend', text);
   }
 
-  void addHtml(String text) {
+  void appendHtml(String text) {
     this.insertAdjacentHTML('beforeend', text);
   }
 
   // If we can come up with a semi-reasonable default value for an Element
   // getter, we'll use it. In general, these return the same values as an
   // element that has no parent.
   String get contentEditable => "false";
   bool get isContentEditable => false;
   bool get draggable => false;
   bool get hidden => false;
@@ skipping 129 matching lines @@
       "WebKit drop zone can't be set for document fragments.");
   }
 
   void set webkitRegionOverflow(String value) {
     throw new UnsupportedError(
       "WebKit region overflow can't be set for document fragments.");
   }
 
 $!MEMBERS
 }