Add List.asMap().

tools/dom/templates/html/impl/impl_Node.darttemplate

 // 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.
 
 part of $LIBRARYNAME;
 
 /**
  * Lazy implementation of the child nodes of an element that does not request
  * the actual child nodes of an element until strictly necessary greatly
  * improving performance for the typical cases where it is not required.
@@ skipping 229 matching lines @@
   // TODO(jacobr): benchmark whether this is more efficient or whether caching
   // a local copy of $dom_childNodes is more efficient.
   int get length => _this.$dom_childNodes.length;
 
   void set length(int value) {
     throw new UnsupportedError(
         "Cannot set length on immutable List.");
   }
 
   Node operator[](int index) => _this.$dom_childNodes[index];
+
+  Map<int, Node> asMap() => IterableMixinWorkaround.asMapList(this);
 }
 
 $(ANNOTATIONS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
   List<Node> get nodes {
     return new _ChildNodeListLazy(this);
   }
 
   void set nodes(Collection<Node> value) {
     // Copy list first since we don't want liveness during iteration.
     // TODO(jacobr): there is a better way to do this.
@@ skipping 26 matching lines @@
       final Node parent = this.parentNode;
       parent.$dom_replaceChild(otherNode, this);
     } catch (e) {
 
     };
     return this;
   }
 
 $!MEMBERS
 }