Added json result of test output to output debug directory.

tools/testing/dart/test_runner.dart

Index: tools/testing/dart/test_runner.dart
diff --git a/tools/testing/dart/test_runner.dart b/tools/testing/dart/test_runner.dart
index 890b02acccbc1a2d53776d0deb90f887a5f3632d..2a409ac4885b50d25f6b45603f964fd28c2df0b3 100644
--- a/tools/testing/dart/test_runner.dart
+++ b/tools/testing/dart/test_runner.dart
@@ -1649,7 +1649,7 @@ class ProcessQueue {
 
   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();
   }