Make ElementList return ElementLists.

client/html/src/ElementWrappingImplementation.dart

 // 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.
 
 // TODO(jacobr): use Lists.dart to remove some of the duplicated functionality.
 class _ChildrenElementList implements ElementList {
   // Raw Element.
   final _element;
   final _childElements;
 
@@ skipping 10 matching lines @@
   }
 
   Element get first() {
     return LevelDom.wrapElement(_element.firstElementChild);
   }
 
   void forEach(void f(Element element)) => _toList().forEach(f);
 
   Collection map(f(Element element)) => _toList().map(f);
 
-  Collection<Element> filter(bool f(Element element)) => _toList().filter(f);
+  ElementList filter(bool f(Element element)) =>
+    new _ElementList(_toList().filter(f));
 
   bool every(bool f(Element element)) {
     for(Element element in this) {
       if (!f(element)) {
         return false;
       }
     };
     return true;
   }
 
@@ skipping 53 matching lines @@
   void setRange(int start, int length, List from, [int startFrom = 0]) =>
     Lists.setRange(this, start, length, from, startFrom);
 
   void removeRange(int start, int length) =>
     Lists.removeRange(this, start, length, (i) => this[i].remove());
 
   void insertRange(int start, int length, [initialValue = null]) {
     throw const NotImplementedException();
   }
 
-  List getRange(int start, int length) => Lists.getRange(this, start, length);
+  ElementList getRange(int start, int length) =>
+    new _ElementList(Lists.getRange(this, start, length));
 
   int indexOf(Element element, [int start = 0]) {
     return Lists.indexOf(this, element, start, this.length);
   }
 
   int lastIndexOf(Element element, [int start = null]) {
     if (start === null) start = length - 1;
     return Lists.lastIndexOf(this, element, start);
   }
 
@@ skipping 32 matching lines @@
   }
 
   Element get first() {
     return this[0];
   }
 
   void forEach(void f(Element element)) => _toList().forEach(f);
 
   Collection map(f(Element element)) => _toList().map(f);
 
-  Collection<Element> filter(bool f(Element element)) => _toList().filter(f);
+  ElementList filter(bool f(Element element)) =>
+    new _ElementList(_toList().filter(f));
 
   bool every(bool f(Element element)) {
     for(Element element in this) {
       if (!f(element)) {
         return false;
       }
     };
     return true;
   }
 
@@ skipping 54 matching lines @@
   }
 
   void removeRange(int start, int length) {
     throw const UnsupportedOperationException('');
   }
 
   void insertRange(int start, int length, [initialValue = null]) {
     throw const UnsupportedOperationException('');
   }
 
-  List getRange(int start, int length) => Lists.getRange(this, start, length);
+  ElementList getRange(int start, int length) =>
+    new _ElementList(Lists.getRange(this, start, length));
 
   int indexOf(Element element, [int start = 0]) =>
     Lists.indexOf(this, element, start, this.length);
 
   int lastIndexOf(Element element, [int start = null]) {
     if (start === null) start = length - 1;
     return Lists.lastIndexOf(this, element, start);
   }
 
   void clear() {
@@ skipping 26 matching lines @@
 
     return _list[_index++];
   }
 
   /**
    * Returns whether the [Iterator] has elements left.
    */
   bool hasNext() => _index < _list.length;
 }
 
+class _ElementList extends _ListWrapper<Element> implements ElementList {
+  _ElementList(List<Element> list) : super(list);
+
+  ElementList filter(bool f(Element element)) =>
+    new _ElementList(super.filter(f));
+
+  ElementList getRange(int start, int length) =>
+    new _ElementList(super.getRange(start, length));
+}
+
 class ElementAttributeMap implements Map<String, String> {
 
   final _element;
 
   ElementAttributeMap._wrap(this._element);
 
   bool containsValue(String value) {
     final attributes = _element.attributes;
     for (int i = 0, len = attributes.length; i < len; i++) {
       if(value == attributes.item(i).value) {
@@ skipping 471 matching lines @@
 
   ElementEvents get on() {
     if (_on === null) {
       _on = new ElementEventsImplementation._wrap(_ptr);
     }
     return _on;
   }
 
   Element clone(bool deep) => super.clone(deep);
 }