Reduce test.dart memory usage.

tools/testing/dart/test_progress.dart

Index: tools/testing/dart/test_progress.dart
diff --git a/tools/testing/dart/test_progress.dart b/tools/testing/dart/test_progress.dart
index 6bfa8283abd772d82e166cf0631576b8ab6dac09..54172a11c9bdbcea3e616981df76e8166ace681f 100644
--- a/tools/testing/dart/test_progress.dart
+++ b/tools/testing/dart/test_progress.dart
@@ -526,6 +526,15 @@ class TestFailurePrinter extends EventListener {
   }
 }
 
+class DeleteTestCaseOutput extends EventListener {
+  void done(TestCase test) {
+    for (CommandOutputImpl output in test.commandOutputs.values) {
+      output.stdout = null;
+      output.stderr = null;
+    }
+  }

[kustermann, 2014/04/11 15:17:37]

I think you shouldn't do that. If two test cases (e.g. dart2js-ff and
dart2js-chrome) share the same compilation command, and one of them finished,
you can't delete the output: If the other one fails and you print the output,
the compilation output will be null!

[Bill Hesse, 2014/04/23 14:52:41]

Removing the code that deletes test output.  Leaving just the minor changes in
this cl.

+}
+
 class ProgressIndicator extends EventListener {
   ProgressIndicator(this._startTime);