Migrate test block 7 to Dart 2.0.

tests/corelib_2/error_stack_trace2_test.dart

 // Copyright (c) 2013, 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 "package:expect/expect.dart";
 
 class A {
   get foo => cyclicStatic;
 }
 
 var a = new A();
 dynamic cyclicStatic = (() => a.foo + 1)();
 
 cyclicInitialization() {
   return cyclicStatic;
 }
 
 main() {
   bool hasThrown = false;
   try {
     cyclicStatic + 1;
   } catch (e2) {
     var e = e2;
     hasThrown = true;
     Expect.isTrue(
         e.stackTrace is StackTrace, "$e doesn't have a non-null stack trace");
   }
   Expect.isTrue(hasThrown);
 }