Install barback from a hosted source in all tests.

test/transformer/can_log_messages_test.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS d.file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library pub_tests;
 
 import 'package:pub/src/exit_codes.dart' as exit_codes;
 import 'package:scheduled_test/scheduled_test.dart';
 import 'package:scheduled_test/scheduled_stream.dart';
 
@@ skipping 21 matching lines @@
     return transform.primaryInput.readAsString().then((contents) {
       var id = transform.primaryInput.id.changeExtension(".out");
       transform.addOutput(new Asset.fromString(id, "\$contents.out"));
     });
   }
 }
 """;
 
 main() {
   integration("can log messages", () {
+    serveBarback();
+
     d.dir(appPath, [
       d.pubspec({
         "name": "myapp",
-        "transformers": ["myapp/src/transformer"]
+        "transformers": ["myapp/src/transformer"],
+        "dependencies": {"barback": "any"}
       }),
       d.dir("lib", [d.dir("src", [
         d.file("transformer.dart", TRANSFORMER)
       ])]),
       d.dir("web", [
         d.file("foo.txt", "foo")
       ])
     ]).create();
 
-    createLockFile('myapp', pkg: ['barback']);
-
+    pubGet();
     var pub = startPub(args: ["build"]);
     pub.stdout.expect(startsWith("Loading source assets..."));
     pub.stdout.expect(consumeWhile(matches("Loading .* transformers...")));
     pub.stdout.expect(startsWith("Building myapp..."));
 
     pub.stdout.expect(emitsLines("""
 [Rewrite on myapp|web/foo.txt]:
 info!"""));
 
     pub.stderr.expect(emitsLines("""
@@ skipping 13 matching lines @@
 
     // In barback >=0.15.0, the span will point to the location where the error
     // occurred.
     pub.stderr.expect(allow(inOrder(["d", "^"])));
 
     pub.stderr.expect("Build failed.");
 
     pub.shouldExit(exit_codes.DATA);
   });
 }