Install barback from a hosted source in all tests.

test/transformer/can_use_read_input_test.dart

Index: test/transformer/can_use_read_input_test.dart
diff --git a/test/transformer/can_use_read_input_test.dart b/test/transformer/can_use_read_input_test.dart
index 89b763b32f721162aba6ce2c9a99eb241010148a..9a7daee7c19cf2d15c24d8918e412748ed38ebb2 100644
--- a/test/transformer/can_use_read_input_test.dart
+++ b/test/transformer/can_use_read_input_test.dart
@@ -30,24 +30,26 @@ class RewriteTransformer extends Transformer {
 """;
 
 main() {
-  integration("a transform can use readInputAsString", () {
-    d.dir(appPath, [
-      d.pubspec({
-        "name": "myapp",
-        "transformers": ["myapp/src/transformer"]
-      }),
-      d.dir("lib", [d.dir("src", [
-        d.file("transformer.dart", TRANSFORMER)
-      ])]),
-      d.dir("web", [
-        d.file("foo.txt", "foo")
-      ])
-    ]).create();
-
-    createLockFile('myapp', pkg: ['barback']);
-
-    pubServe();
-    requestShouldSucceed("foo.out", "[[102, 111, 111]].out");
-    endPubServe();
-  });
+   integration("a transform can use readInputAsString", () {
+     serveBarback();
+
+     d.dir(appPath, [
+       d.pubspec({
+         "name": "myapp",
+         "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();
+
+     pubGet();
+     pubServe();
+     requestShouldSucceed("foo.out", "[[102, 111, 111]].out");
+     endPubServe();
+   });
 }