Add tests for BuildGroup names

tools/gardening/test/test_client.dart

Index: tools/gardening/test/test_client.dart
diff --git a/tools/gardening/test/test_client.dart b/tools/gardening/test/test_client.dart
index 679ddcc11a3847433fda90ce169944bb547907ae..d84cbb17a8d905ef96572e18bbad86e144f8fab8 100644
--- a/tools/gardening/test/test_client.dart
+++ b/tools/gardening/test/test_client.dart
@@ -33,8 +33,7 @@ class TestClient implements BuildbotClient {
     String path = computePath(buildUri);
     File file = new File.fromUri(Platform.script.resolve(path));
     if (!file.existsSync() && _client != null) {
-      await file.parent.create();
-      log('Pulling $buildUri from http');
+      await file.parent.create(recursive: true);
       BuildResult result = await _client.readResult(buildUri);
       if (result.buildNumber != null) {
         print('Writing test data to $file');