Drop support for older Barback versions.

test/transformer/configuration/passes_configuration_to_a_transformer_test.dart

Index: test/transformer/configuration/passes_configuration_to_a_transformer_test.dart
diff --git a/test/transformer/configuration/passes_configuration_to_a_transformer_test.dart b/test/transformer/configuration/passes_configuration_to_a_transformer_test.dart
index c1ace808befca15f94244fc220fa6bb0145ed236..14533eb6335475edb5b9406f58edfe7c91e5d7d6 100644
--- a/test/transformer/configuration/passes_configuration_to_a_transformer_test.dart
+++ b/test/transformer/configuration/passes_configuration_to_a_transformer_test.dart
@@ -34,28 +34,26 @@ class ConfigTransformer extends Transformer {
 """;
 
 main() {
-  withBarbackVersions("any", () {
-    integration("passes configuration to a transformer", () {
-      var configuration = {"param": ["list", "of", "values"]};
-
-      d.dir(appPath, [
-        d.pubspec({
-          "name": "myapp",
-          "transformers": [{"myapp/src/transformer": configuration}]
-        }),
-        d.dir("lib", [d.dir("src", [
-          d.file("transformer.dart", transformer)
-        ])]),
-        d.dir("web", [
-          d.file("foo.txt", "foo")
-        ])
-      ]).create();
-
-      createLockFile('myapp', pkg: ['barback']);
-
-      var server = pubServe();
-      requestShouldSucceed("foo.json", JSON.encode(configuration));
-      endPubServe();
-    });
-  });
+   integration("passes configuration to a transformer", () {
+     var configuration = {"param": ["list", "of", "values"]};
+
+     d.dir(appPath, [
+       d.pubspec({
+         "name": "myapp",
+         "transformers": [{"myapp/src/transformer": configuration}]
+       }),
+       d.dir("lib", [d.dir("src", [
+         d.file("transformer.dart", transformer)
+       ])]),
+       d.dir("web", [
+         d.file("foo.txt", "foo")
+       ])
+     ]).create();
+
+     createLockFile('myapp', pkg: ['barback']);
+
+     var server = pubServe();
+     requestShouldSucceed("foo.json", JSON.encode(configuration));
+     endPubServe();
+   });
 }