unittest fix: Get rid of the deprecation of IllegalJsRegexException's matcher.

pkg/unittest/test/matchers_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.
 
 library unittestTests;
 import 'package:unittest/unittest.dart';
 import 'dart:async';
 part 'test_utils.dart';
 
 doesNotThrow() {}
@@ skipping 140 matching lines @@
     test('throwsArgumentError', () {
       shouldPass(() { throw new ArgumentError(''); },
           throwsArgumentError);
       shouldFail(() { throw new Exception(); },
           throwsArgumentError,
         "Expected: throws an exception which matches ArgumentError "
         "but:  exception <Exception> does not match "
             "ArgumentError.");
     });
 
-    test('throwsIllegalJSRegExpException', () {
-      shouldPass(() { throw new IllegalJSRegExpException('',''); },
-          throwsIllegalJSRegExpException);
-      shouldFail(() { throw new Exception(); },
-          throwsIllegalJSRegExpException,
-        "Expected: throws an exception which matches IllegalJSRegExpException "
-        "but:  exception <Exception> does not match "
-            "IllegalJSRegExpException.");
-    });
-
     test('throwsRangeError', () {
       shouldPass(() { throw new RangeError(0); },
           throwsRangeError);
       shouldFail(() { throw new Exception(); },
           throwsRangeError,
         "Expected: throws an exception which matches RangeError "
         "but:  exception <Exception> does not match RangeError.");
     });
 
     test('throwsNoSuchMethodError', () {
@@ skipping 531 matching lines @@
       var w = new Widget();
       w.price = 10;
       shouldPass(w, new HasPrice(greaterThan(0)));
       shouldFail(w, new HasPrice(greaterThan(10)),
           'Expected: Widget with a price that is a value greater than <10> '
           'but: price was <10>.');
     });
   });
 }