Install barback from a hosted source in all tests.

test/global/run/runs_transformer_test.dart

Index: test/global/run/runs_transformer_test.dart
diff --git a/test/global/run/runs_transformer_test.dart b/test/global/run/runs_transformer_test.dart
index ac0489b9277fb9d765e670b19e5c8ff34d6f50ec..ec4c0fe18e6753b4494a229df2676783cc720772 100644
--- a/test/global/run/runs_transformer_test.dart
+++ b/test/global/run/runs_transformer_test.dart
@@ -25,20 +25,23 @@ class DartTransformer extends Transformer {
 
 main() {
   integration('runs a global script generated by a transformer', () {
-    makeGlobalPackage("foo", "1.0.0", [
-      d.pubspec({
-        "name": "foo",
-        "version": "1.0.0",
-        "transformers": ["foo/src/transformer"]
-      }),
-      d.dir("lib", [d.dir("src", [
-        d.file("transformer.dart", TRANSFORMER),
-        d.file("primary.in", "")
-      ])])
-    ], pkg: ['barback']);
+    servePackages((builder) {
+      builder.serveRealPackage("barback");
+
+      builder.serve("foo", "1.0.0",
+          pubspec: {"transformers": ["foo/src/transformer"]},
+          deps: {"barback": "any"},
+          contents: [
+            d.dir("lib", [d.dir("src", [
+              d.file("transformer.dart", TRANSFORMER),
+              d.file("primary.in", "")
+            ])])
+          ]);
+    });
+
+    schedulePub(args: ["global", "activate", "foo"]);
 
     var pub = pubRun(global: true, args: ["foo:script"]);
-
     pub.stdout.expect("generated");
     pub.shouldExit();
   });