Added new version of reduce.

sdk/lib/html/html_common/filtered_element_list.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.
 
 part of html_common;
 
 /**
  * An indexable collection of a node's descendants in the document tree,
  * filtered so that only elements are in the collection.
  */
@@ skipping 123 matching lines @@
   }
 
   void removeWhere(bool test(Element element)) {
     IterableMixinWorkaround.removeWhere(this, test);
   }
 
   void retainWhere(bool test(Element element)) {
     IterableMixinWorkaround.retainWhere(this, test);
   }
 
-  dynamic reduce(dynamic initialValue,
-      dynamic combine(dynamic previousValue, Element element)) {
-    return _filtered.reduce(initialValue, combine);
+  Element reduce(Element combine(Element value, Element element)) {
+    return _filtered.reduce(combine);
   }
 
   dynamic fold(dynamic initialValue,
       dynamic combine(dynamic previousValue, Element element)) {
-    return IterableMixinWorkaround.fold(this, initialValue, combine);
+    return _filtered.fold(initialValue, combine);
   }
 
   bool every(bool f(Element element)) => _filtered.every(f);
   bool any(bool f(Element element)) => _filtered.any(f);
   List<Element> toList({ bool growable: true }) =>
       new List<Element>.from(this, growable: growable);
   Set<Element> toSet() => new Set<Element>.from(this);
   Element firstWhere(bool test(Element value), {Element orElse()}) {
     return _filtered.firstWhere(test, orElse: orElse);
   }
@@ skipping 49 matching lines @@
   Element get single => _filtered.single;
 
   Element min([int compare(Element a, Element b)]) => _filtered.min(compare);
 
   Element max([int compare(Element a, Element b)]) => _filtered.max(compare);
 
   Map<int, Element> asMap() {
     return IterableMixinWorkaround.asMapList(this);
   }
 }