Fix issue 1146: skip regular Mint test in 64 bit. Add Mint test for 64 bit.

tests/standalone/medium_integer_test.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.
 // Testing Mints. Note that the tests may not work on 64-bit machines,
 // as Smi's would be used to represent many of the numbers.
 
 #library("MediumIntegerTest.dart");
 #import("dart:coreimpl");
 
+
 class MediumIntegerTest {
 
   static void checkSmi(int a) {
-    Expect.equals(true, (a is Smi));
+    Expect.isTrue(a is Smi);
   }
 
   static void checkMint(int a) {
-    Expect.equals(true, (a is Mint));
+    if (runsOn32Bit) {
+      Expect.isTrue(a is Mint);
+    }
   }
 
   static void checkBigint(int a) {
-    Expect.equals(true, (a is Bigint));
+    Expect.isTrue(a is Bigint);
   }
 
   static int getMint() {
     return 1234567890123456789;
   }
 
   static testSmiOverflow() {
      int a = 1073741823;
      int b = 1073741822;
      checkSmi(a);
@@ skipping 98 matching lines @@
     Expect.equals(4611686018427387904000000000000000000, a * b);
   }
 
   static testMintAnd(mint) {
     // Issue 1845.
     final int t = 0;
     var res = mint & (t - 1);
     Expect.equals(mint, res);
   }
 
-  // TODO(srdjan): Add more tests.
+  // Mint both in 32- and 64-bit architecture.
+  static void testAlwaysMint() {
+    var a = 4611686018427390000;
+    Expect.isTrue(a is Mint);
+  }
 
   static void testMain() {
     checkMint(getMint());
     Expect.equals(1234567890123456789, getMint());
     testSmiOverflow();
     testMintAdd();
     testMintSub();
     testMintMul();
     testMintDiv();
     testMintAnd(-1925149952);
     testMintAnd(1925149952);
     var a = 100000000000;
     var b = 100000000001;
     checkMint(a);
     checkMint(b);
     Expect.equals(false, a.hashCode() == b.hashCode());
     Expect.equals(true, a.hashCode() == (b - 1).hashCode());
+    testAlwaysMint();
   }
 }
 
+bool runsOn32Bit;
+
 main() {
+  runsOn32Bit = 4294967295 is Mint;
   for (int i = 0; i < 1000; i++) {
     MediumIntegerTest.testMain();
   }
 }