Fix some warnings in the core library identified by the static analyzer.

corelib/src/future.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.
 
 /**
  * A [Future] is used to obtain a value sometime in the future.  Receivers of a
  * [Future] can obtain the value by passing a callback to [then]. For example:
  *
  *     Future<int> future = getFutureFromSomewhere();
  *     future.then((value) {
@@ skipping 183 matching lines @@
    * returned future will be a list of all the values that were produced.)
    */
   static Future<List> wait(List<Future> futures) {
     if (futures.isEmpty()) {
       return new Future<List>.immediate(const []);
     }
 
     Completer completer = new Completer<List>();
     Future<List> result = completer.future;
     int remaining = futures.length;
-    List<Object> values = new List(futures.length);
+    List values = new List(futures.length);
 
     // As each future completes, put its value into the corresponding
     // position in the list of values.
     for (int i = 0; i < futures.length; i++) {
       // TODO(mattsh) - remove this after bug
       // http://code.google.com/p/dart/issues/detail?id=333 is fixed.
       int pos = i;
       Future future = futures[pos];
       future.then((Object value) {
         values[pos] = value;
         if (--remaining == 0 && !result.isComplete) {
           completer.complete(values);
         }
       });
       future.handleException((exception) {
         if (!result.isComplete) completer.completeException(exception);
         return true;
       });
     }
     return result;
   }
 }