Make pubspec.lock keep relative path if it is originally specified as relative in pubspec.yaml (iss…

sdk/lib/_internal/pub/test/get/path/relative_path_test.dart

Index: sdk/lib/_internal/pub/test/get/path/relative_path_test.dart
diff --git a/sdk/lib/_internal/pub/test/get/path/relative_path_test.dart b/sdk/lib/_internal/pub/test/get/path/relative_path_test.dart
index 8313f3e98db5ffa61b1627b1dd0b529a5943dbcb..040ba7d56a18935054e73d632d73ffb2b8d7a67e 100644
--- a/sdk/lib/_internal/pub/test/get/path/relative_path_test.dart
+++ b/sdk/lib/_internal/pub/test/get/path/relative_path_test.dart
@@ -2,6 +2,12 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE d.file.
 
+import 'package:path/path.dart' as path;
+import 'package:scheduled_test/scheduled_test.dart';
+import 'package:unittest/unittest.dart';
+
+import '../../../lib/src/lock_file.dart';
+import '../../../lib/src/source_registry.dart';
 import '../../descriptor.dart' as d;
 import '../../test_pub.dart';
 
@@ -59,4 +65,27 @@ main() {
       ])
     ]).validate();
   });
+  
+  integration("relative path preserved in the lockfile", () {
+    d.dir("foo", [
+      d.libDir("foo"),
+      d.libPubspec("foo", "0.0.1")
+    ]).create();
+
+    d.dir(appPath, [
+      d.appPubspec({
+        "foo": {"path": "../foo"}
+      })
+    ]).create();
+
+    pubGet();
+
+    schedule(() {
+      var lockfilePath = path.join(sandboxDir, appPath, "pubspec.lock");
+      var lockfile = new LockFile.load(lockfilePath, new SourceRegistry());
+      var description = lockfile.packages["foo"].description;
+
+      expect(path.isRelative(description["path"]), isTrue);
+    });
+  });
 }