Catch illegally declared constructors

tests/language/bad_constructor_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.
+
+
+class A {
+  // Constructor may not be static.
+  static A();  /// 00: compile-time error
+
+  // Factory may not be static.
+  static factory A() { return null; }  /// 01: compile-time error
+
+  // Constructor may not be abstract.
+  abstract A();  /// 02: compile-time error
+
+  // Factory may not be abstract
+  abstract factory A() { return null; }  /// 03: compile-time error
+}
+
+main() {
+  new A();
+}