Port and integrate the irregexp engine from V8

tests/language/regex/early-acid3-86_test.dart

+// Copyright (c) 2014, 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 'util.dart';
+import 'package:expect/expect.dart';
+
+void main() {
+  description(
+  'Test that covers capturing brackets, and was adapted from a part of an early version of Acid3.'
+  );
+
+  // JS regexps aren't like Perl regexps, if their character
+  // classes start with a ] that means they're empty. So this
+  // is a syntax error; if we get here it's a bug.
+  assertThrows(() => new RegExp(r"TA[])]").firstMatch('TA]'));
+  shouldBeNull(new RegExp(r"[]").firstMatch(''));
+  shouldBe(new RegExp(r"(\3)(\1)(a)").firstMatch('cat'), ['a', '', '', 'a']);
+}