Write .test-outcome.log files for test.py

dart/tools/bots/cross-vm.py

Index: dart/tools/bots/cross-vm.py
diff --git a/dart/tools/bots/cross-vm.py b/dart/tools/bots/cross-vm.py
index 08ae335a99cb5f807daf8564529db9bbe94b532c..82e46d8e6ff06ca51b58c190e22786fa554b2ae9 100644
--- a/dart/tools/bots/cross-vm.py
+++ b/dart/tools/bots/cross-vm.py
@@ -70,7 +70,7 @@ def target_builder(arch, mode):
   test_py = os.path.join('tools', 'test.py')
   test_args = [sys.executable, test_py, '--progress=line', '--report',
                '--time', '--compiler=none', '--runtime=vm', '--write-debug-log',
-               '--mode=' + mode, '--arch=' + arch]
+               '--write-test-outcome-log', '--mode=' + mode, '--arch=' + arch]
 
   revision = int(os.environ['BUILDBOT_GOT_REVISION'])
   tarball = tarball_name(arch, mode, revision)
@@ -87,7 +87,7 @@ def target_builder(arch, mode):
       run(test_args)
 
     with bot.BuildStep('execute checked_tests'):
-      run(test_args + ['--checked'])
+      run(test_args + ['--checked', '--append_logs')
   finally:
     for path in temporary_files:
       if os.path.exists(path):