Added json result of test output to output debug directory.

tools/testing/dart/test_runner.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.
 
 /**
  * Classes and methods for executing tests.
  *
  * This module includes:
  * - Managing parallel execution of tests, including timeout checks.
  * - Evaluating the output of each test as pass/fail/crash/timeout.
@@ skipping 1631 matching lines @@
   }
 
   void eventAllTestsKnown() {
     for (var listener in _eventListener) {
       listener.allTestsKnown();
     }
   }
 
   void eventAllTestsDone() {
     for (var listener in _eventListener) {
-      listener.allDone();
+      listener.allDone(_globalConfiguration);

[Bill Hesse, 2017/09/01 11:56:14]

I think we can avoid this.  The one thing we need (the output log directory) can
be set in the when the listener is registered.

[mkroghj, 2017/09/04 10:43:35]

Done.

     }
     _allDone();
   }
 }