Change getRange to sublist. Make getRange deprecated.

sdk/lib/_collection_dev/list.dart

 // Copyright (c) 2013, 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 dart._collection.dev;
 
 /**
  * Class implementing the read-operations on [List].
  *
  * Implements all read-only operations, except [:operator[]:] and [:length:],
@@ skipping 11 matching lines @@
 
   // Iterable interface.
   E elementAt(int index) {
     return this[index];
   }
 
   Map<int, E> asMap() {
     return new ListMapView(this);
   }
 
-  List<E> getRange(int start, int length) {
+  List<E> sublist(int start, [int end]) {
+    if (end == null) end = length;
     if (start < 0 || start > this.length) {
       throw new RangeError.range(start, 0, this.length);
     }
-    if (length < 0 || start + length > this.length) {
-      throw new RangeError.range(length, 0, this.length - start);
+    if (end < start || end > this.length) {
+      throw new RangeError.range(end, start, this.length);
     }
-    List<E> result = new List<E>(length);
+    int length = end - start;
+    List<E> result = new List<E>()..length = length;
     for (int i = 0; i < length; i++) {
       result[i] = this[start + i];
     }
     return result;
   }
 
+  List<E> getRange(int start, int length) => sublist(start, start + length);
+
   int indexOf(E element, [int start = 0]) {
     return Arrays.indexOf(this, element, start, this.length);
   }
 
   int lastIndexOf(E element, [int start = null]) {
     if (start == null) start = length - 1;
     return Arrays.lastIndexOf(this, element, start);
   }
 
   Iterable<E> get reversed => new ReversedListIterable(this);
@@ skipping 272 matching lines @@
   }
 
   E remove(int key) {
     throw new UnsupportedError("Cannot modify an unmodifiable map");
   }
 
   void clear() {
     throw new UnsupportedError("Cannot modify an unmodifiable map");
   }
 }