Expose aggregate transformers in barback.

pkg/barback/test/package_graph/declaring_transformer_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS 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 barback.test.package_graph.declaring_transformer_test;
 
 import 'package:barback/barback.dart';
 import 'package:barback/src/utils.dart';
 import 'package:scheduled_test/scheduled_test.dart';
 
@@ skipping 285 matching lines @@
    ]]});
 
    updateSources(["app|foo.txt"]);
    expectNoAsset("app|out.txt");
    expectAsset("app|foo.txt", "foo");
    buildShouldFail([isTransformerException(BadTransformer.ERROR)]);
   });
 
   test("can emit outputs it didn't declare", () {
     initGraph(["app|foo.txt"], {"app": [
-      [new DeclareAssetsTransformer([], ["app|out.txt"])]
+      [new DeclareAssetsTransformer([], emitted: ["app|out.txt"])]
     ]});
 
     updateSources(["app|foo.txt"]);
     // There's probably going to be some time when "out.txt" is unavailable,
     // since it was undeclared.
     schedule(pumpEventQueue);
     expectAsset("app|out.txt", "app|out.txt");
     buildShouldSucceed();
   });
 
   test("can overwrite the primary input even if it declared that it wouldn't",
       () {
-    var transformer = new DeclareAssetsTransformer([], ["app|foo.txt"]);
+    var transformer = new DeclareAssetsTransformer(
+        [], emitted: ["app|foo.txt"]);
     initGraph(["app|foo.txt"], {"app": [[transformer]]});
 
     transformer.pauseApply();
     updateSources(["app|foo.txt"]);
     expectAsset("app|foo.txt", "foo");
 
     transformer.resumeApply();
     schedule(pumpEventQueue);
     expectAsset("app|foo.txt", "app|foo.txt");
     buildShouldSucceed();
   });
 
   test("can declare outputs it doesn't emit", () {
     initGraph(["app|foo.txt"], {"app": [
-      [new DeclareAssetsTransformer(["app|out.txt"], [])]
+      [new DeclareAssetsTransformer(["app|out.txt"], emitted: [])]
     ]});
 
     updateSources(["app|foo.txt"]);
     expectNoAsset("app|out.txt");
     buildShouldSucceed();
   });
 }