Port and integrate the irregexp engine from V8

tests/language/regex/compile_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 RegExp.compile method.'
+  );
+
+  var re = new RegExp("a", caseSensitive: false);
+  shouldBeTrue(re.hasMatch('A'));
+  shouldBeFalse(re.isMultiLine);
+  shouldBeFalse(re.isCaseSensitive);
+
+  re = new RegExp("a");
+  shouldBeFalse(re.isMultiLine);
+  shouldBeTrue(re.isCaseSensitive);
+  shouldBeFalse(re.hasMatch('A'));
+
+  assertThrows(() => new RegExp('+'));
+}