Drop support for older Barback versions.

test/transformer/configuration/with_configuration_only_instantiates_configurable_transformers_test.dart

Index: test/transformer/configuration/with_configuration_only_instantiates_configurable_transformers_test.dart
diff --git a/test/transformer/configuration/with_configuration_only_instantiates_configurable_transformers_test.dart b/test/transformer/configuration/with_configuration_only_instantiates_configurable_transformers_test.dart
index 9f66dc00761177a31b6a004bd818479fb9242021..000c8b552a7f4029db65d754cf5f5310b5363836 100644
--- a/test/transformer/configuration/with_configuration_only_instantiates_configurable_transformers_test.dart
+++ b/test/transformer/configuration/with_configuration_only_instantiates_configurable_transformers_test.dart
@@ -47,30 +47,28 @@ class RewriteTransformer extends Transformer {
 """;
 
 main() {
-  withBarbackVersions("any", () {
-     integration("with configuration, only instantiates configurable "
-         "transformers", () {
-       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));
-       requestShould404("foo.out");
-       endPubServe();
-     });
-  });
+   integration("with configuration, only instantiates configurable "
+       "transformers", () {
+     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));
+     requestShould404("foo.out");
+     endPubServe();
+   });
 }