Revert "Remove Expect from core library."

tests/language/deopt_smi_op_test.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.
 
-import "package:expect/expect.dart";
-
 // Test hoisted (loop-invariant) smi operations with deoptimization.
 
 test_mul(h)  {
   var x;
   for (var i=0; i<3; i++) {
     x = h * 100000;
   }
   return x;
 }
 
 test_neg(h)  {
   var x;
   for (var i=0; i<3; i++) {
     x = -h;
   }
   return x;
 }
 
 main() {
   for (var i=0; i<10000; i++) test_mul(10);
   Expect.equals(1000000, test_mul(10));
   Expect.equals(100000000000, test_mul(1000000));
   Expect.equals(100000 * 0x3fffffffffffffff, test_mul(0x3fffffffffffffff));
 
   for (var i=0; i<10000; i++) test_neg(10);
   Expect.equals(-10, test_neg(10));
   Expect.equals(0x40000000, test_neg(-0x40000000));
   Expect.equals(0x4000000000000000, test_neg(-0x4000000000000000));
 }