Adjust some tests for limited 64-bit integers

tests/corelib_strong/hash_set_test.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.
 //
 // VMOptions=
 
 // Tests of hash set behavior, with focus in iteration and concurrent
 // modification errors.
 
 library hash_map2_test;
@@ skipping 257 matching lines @@
     Expect.identical(1, set.lookup(1.0));
     set.add(-0.0);
     Expect.identical(-0.0, set.lookup(0.0));
   }
 
   {
     // Test special hash codes
     Set set = newSet();
     List keys = [];
     // Powers of two
-    for (int i = 65; i >= 2; --i) {
+    for (int i = 63; i >= 2; --i) {
       keys.add(new Mutable(math.pow(2, i)));
     }
     for (var key in keys) {
       Expect.isTrue(set.add(key));
     }
     for (var key in keys) {
       Expect.isTrue(set.contains(key));
     }
   }
 }
@@ skipping 65 matching lines @@
   // Can't make a bad compareTo that isn't invalid.
   int compareTo(BadHashCode other) => id - other.id;
 }
 
 class Mutable {
   int id;
   Mutable(this.id);
   int get hashCode => id;
   bool operator ==(other) => other is Mutable && id == other.id;
 }