Fix some warnings.

lib/dom/templates/html/impl/impl_NodeList.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.
 
 // TODO(nweiz): when all implementations we target have the same name for the
 // coreimpl implementation of List<E>, extend that rather than wrapping.
 class _ListWrapper<E> implements List<E> {
   List _list;
 
   _ListWrapper(List this._list);
@@ skipping 32 matching lines @@
 
   int lastIndexOf(E element, [int start = 0]) =>
     _list.lastIndexOf(element, start);
 
   void clear() => _list.clear();
 
   E removeLast() => _list.removeLast();
 
   E last() => _list.last();
 
-  List<E> getRange(int start, int length) => _list.getRange(start, length);
+  List<E> getRange(int start, int rangeLength) =>
+    _list.getRange(start, rangeLength);
 
-  void setRange(int start, int length, List<E> from, [int startFrom = 0]) =>
-    _list.setRange(start, length, from, startFrom);
+  void setRange(int start, int rangeLength, List<E> from, [int startFrom = 0])
+      => _list.setRange(start, rangeLength, from, startFrom);
 
-  void removeRange(int start, int length) => _list.removeRange(start, length);
+  void removeRange(int start, int rangeLength) =>
+    _list.removeRange(start, rangeLength);
 
-  void insertRange(int start, int length, [E initialValue = null]) =>
-    _list.insertRange(start, length, initialValue);
+  void insertRange(int start, int rangeLength, [E initialValue = null]) =>
+    _list.insertRange(start, rangeLength, initialValue);
 
   E get first() => _list[0];
 }
 
 /**
  * This class is used to insure the results of list operations are NodeLists
  * instead of lists.
  */
 class _NodeListWrapper extends _ListWrapper<Node> implements NodeList {
   _NodeListWrapper(List list) : super(list);
 
   NodeList filter(bool f(Node element)) =>
     new _NodeListWrapper(_list.filter(f));
 
-  NodeList getRange(int start, int length) =>
-    new _NodeListWrapper(_list.getRange(start, length));
+  NodeList getRange(int start, int rangeLength) =>
+    new _NodeListWrapper(_list.getRange(start, rangeLength));
 }
 
 class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
   _NodeImpl _parent;
 
   // -- start List<Node> mixins.
   // Node is the element type.
 
   // From Iterable<Node>:
 
@@ skipping 14 matching lines @@
     _parent.$dom_appendChild(value);
   }
 
   void addAll(Collection<_NodeImpl> collection) {
     for (_NodeImpl node in collection) {
       _parent.$dom_appendChild(node);      
     }
   }
 
   _NodeImpl removeLast() {
-    final last = this.last();
-    if (last != null) {
-      _parent.$dom_removeChild(last);
+    final result = this.last();
+    if (result != null) {
+      _parent.$dom_removeChild(result);
     }
-    return last;
+    return result;
   }
 
   void clear() {
     _parent.text = '';
   }
 
   void operator []=(int index, _NodeImpl value) {
     _parent.$dom_replaceChild(value, this[index]);
   }
 
@@ skipping 19 matching lines @@
   int indexOf(Node element, [int start = 0]) =>
       _Lists.indexOf(this, element, start, this.length);
 
   int lastIndexOf(Node element, [int start = 0]) =>
       _Lists.lastIndexOf(this, element, start);
 
   Node last() => this[length - 1];
   Node get first() => this[0];
 
   // FIXME: implement thesee.
-  void setRange(int start, int length, List<Node> from, [int startFrom]) {
+  void setRange(int start, int rangeLength, List<Node> from, [int startFrom]) {
     throw new UnsupportedOperationException("Cannot setRange on immutable List.");
   }
-  void removeRange(int start, int length) {
+  void removeRange(int start, int rangeLength) {
     throw new UnsupportedOperationException("Cannot removeRange on immutable List.");
   }
-  void insertRange(int start, int length, [Node initialValue]) {
+  void insertRange(int start, int rangeLength, [Node initialValue]) {
     throw new UnsupportedOperationException("Cannot insertRange on immutable List.");
   }
-  NodeList getRange(int start, int length) =>
-    new _NodeListWrapper(_Lists.getRange(this, start, length, <Node>[]));
+  NodeList getRange(int start, int rangeLength) =>
+    new _NodeListWrapper(_Lists.getRange(this, start, rangeLength, <Node>[]));
 
   // -- end List<Node> mixins.
 
 $!MEMBERS
 }