Add test with implicit super() initializer.

tests/language/src/Constructor4Test.dart

Index: tests/language/src/Constructor4Test.dart
diff --git a/tests/language/src/Constructor4Test.dart b/tests/language/src/Constructor4Test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..ad16fb34136095d5b3eb03c23e0cee544a59274b
--- /dev/null
+++ b/tests/language/src/Constructor4Test.dart
@@ -0,0 +1,35 @@
+// Copyright (c) 2011, 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.
+// Dart test program for constructors and initializers.
+
+// Expect the initializer expressions E(i) to be evaluated
+// in the order 1, 2, 3, ...
+// Each expression must be evaluated exactly once.
+
+String trace = "";
+
+int E(int i) {
+  trace += "$i-";
+  return i;
+}
+
+class A {
+  var a1;
+  A() : a1 = E(2) {
+    E(3);
+  }
+}
+
+class B extends A {
+  var b1;
+  B(x) : b1 = E(1) /* Implicit super call to A's initializers happens here. */ {
+    // Implicit super call to A's body happens here.
+    E(4);
+  }
+}
+
+main() {
+  var b = new B(0);
+  Expect.equals("1-2-3-4-", trace);
+}