Get rid of a lot of () for getters.

lib/coreimpl/regexp.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.
 
 class JSSyntaxRegExp implements RegExp {
   external const JSSyntaxRegExp(String pattern,
                                 [bool multiLine, bool ignoreCase]);
   external Match firstMatch(String str);
   external Iterable<Match> allMatches(String str);
   external bool hasMatch(String str);
   external String stringMatch(String str);
-  external String get pattern();
-  external bool get multiLine();
-  external bool get ignoreCase();
+  external String get pattern;
+  external bool get multiLine;
+  external bool get ignoreCase;
 }