Migrate test block 10 to Dart 2.0.

tests/corelib_strong/integer_to_radix_string_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";
-
-main() {
-  // Test that we accept radix 2 to 36 and that we use lower-case
-  // letters.
-  var expected = [
-    '0',
-    '1',
-    '2',
-    '3',
-    '4',
-    '5',
-    '6',
-    '7',
-    '8',
-    '9',
-    'a',
-    'b',
-    'c',
-    'd',
-    'e',
-    'f',
-    'g',
-    'h',
-    'i',
-    'j',
-    'k',
-    'l',
-    'm',
-    'n',
-    'o',
-    'p',
-    'q',
-    'r',
-    's',
-    't',
-    'u',
-    'v',
-    'w',
-    'x',
-    'y',
-    'z'
-  ];
-  for (var radix = 2; radix <= 36; radix++) {
-    for (var i = 0; i < radix; i++) {
-      Expect.equals(expected[i], i.toRadixString(radix));
-    }
-  }
-
-  var illegalRadices = [-1, 0, 1, 37];
-  for (var radix in illegalRadices) {
-    try {
-      42.toRadixString(radix);
-      Expect.fail("Exception expected");
-    } on ArgumentError catch (e) {
-      // Nothing to do.
-    }
-  }
-
-  // Try large numbers (regression test for issue 15316).
-  var bignums = [
-    0x80000000,
-    0x100000000,
-    0x10000000000000,
-    0x10000000000001, // 53 significant bits.
-    0x20000000000000,
-    0x20000000000002,
-    0x1000000000000000,
-    0x1000000000000100,
-    0x2000000000000000,
-    0x2000000000000200,
-    0x8000000000000000,
-    0x8000000000000800,
-    0x10000000000000000,
-    0x10000000000001000,
-    0x100000000000010000,
-    0x1000000000000100000,
-    0x10000000000001000000,
-    0x100000000000010000000,
-    0x1000000000000100000000,
-    0x10000000000001000000000,
-  ];
-  for (var bignum in bignums) {
-    for (int radix = 2; radix <= 36; radix++) {
-      String digits = bignum.toRadixString(radix);
-      int result = int.parse(digits, radix: radix);
-      Expect.equals(
-          bignum, result, "${bignum.toRadixString(16)} -> $digits/$radix");
-    }
-  }
-}