Make first and last getters.

lib/compiler/implementation/util/uri_extras.dart

 // 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.
 
 #library('uri_extras');
 
 #import('dart:math');
 #import('dart:uri');
 
 String relativize(Uri base, Uri uri, bool isWindows) {
@@ skipping 40 matching lines @@
       // letters or hostnames.
       return uri.path;
     }
     StringBuffer sb = new StringBuffer();
     for (int i = common + 1; i < baseParts.length; i++) {
       sb.add('../');
     }
     for (int i = common; i < uriParts.length - 1; i++) {
       sb.add('${uriParts[i]}/');
     }
-    sb.add('${uriParts.last()}');
+    sb.add('${uriParts.last}');
     return sb.toString();
   }
   return uri.toString();
 }