Fix a lockfile freshness checking bug.

test/must_pub_get_test.dart

Index: test/must_pub_get_test.dart
diff --git a/test/must_pub_get_test.dart b/test/must_pub_get_test.dart
index 058ea89ae27e0681a29eb83ecb80902d80e91753..0381c5bbb3e1c9a6518115b9c249f953ea91e25a 100644
--- a/test/must_pub_get_test.dart
+++ b/test/must_pub_get_test.dart
@@ -293,16 +293,19 @@ foo:http://example.com/
         ]).create();
 
         d.dir(appPath, [
-          d.appPubspec({"foo": {"path": "../foo"}})
-        ]);
+          d.appPubspec({"bar": {"path": "../bar"}})
+        ]).create();
 
         pubGet();
 
-        // Update foo's pubspec without touching the app's.
+        // Update bar's pubspec without touching the app's.
         d.dir("bar", [
           d.libPubspec("bar", "1.0.0", deps: {"foo": "2.0.0"})
         ]).create();
       });
+
+      _requiresPubGet('The pubspec.yaml file has changed since the '
+          'pubspec.lock file was generated, please run "pub get" again.');

[Bob Nystrom, 2016/05/05 22:06:42]

It would be really nice if the error message showed which package's pubspec was
changed. As it is, this is going to very confusingly make people thing the
entrypoint package is the one that changed.

[nweiz, 2016/05/05 22:29:49]

Done.

     });
   });