Don't fetch git repository unnecessarily when running "pub get".

sdk/lib/_internal/pub/test/get/git/doesnt_fetch_if_nothing_changes_test.dart

Index: sdk/lib/_internal/pub/test/get/git/doesnt_fetch_if_nothing_changes_test.dart
diff --git a/sdk/lib/_internal/pub/test/upgrade/git/upgrade_to_nonexistent_pubspec_test.dart b/sdk/lib/_internal/pub/test/get/git/doesnt_fetch_if_nothing_changes_test.dart
similarity index 57%
copy from sdk/lib/_internal/pub/test/upgrade/git/upgrade_to_nonexistent_pubspec_test.dart
copy to sdk/lib/_internal/pub/test/get/git/doesnt_fetch_if_nothing_changes_test.dart
index b9bd476b83a0f1e502dc681eac184f7cffc71564..54cd98c62e249139c31d33629878c382d0868699 100644
--- a/sdk/lib/_internal/pub/test/upgrade/git/upgrade_to_nonexistent_pubspec_test.dart
+++ b/sdk/lib/_internal/pub/test/get/git/doesnt_fetch_if_nothing_changes_test.dart
@@ -1,15 +1,19 @@
-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// 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 pub_tests;
 
+import 'package:path/path.dart' as p;
+import 'package:scheduled_test/scheduled_test.dart';
+
+import '../../../lib/src/io.dart';
 import '../../descriptor.dart' as d;
 import '../../test_pub.dart';
 
 main() {
   initConfig();
-  integration("upgrades Git packages to a nonexistent pubspec", () {
+  integration("doesn't re-fetch a repository if nothing changes", () {
     ensureGit();
 
     var repo = d.git('foo.git', [
@@ -18,7 +22,9 @@ main() {
     ]);
     repo.create();
 
-    d.appDir({"foo": {"git": "../foo.git"}}).create();
+    d.appDir({
+      "foo": {"git": {"url": "../foo.git"}}
+    }).create();
 
     pubGet();
 
@@ -28,11 +34,11 @@ main() {
       ])
     ]).validate();
 
-    repo.runGit(['rm', 'pubspec.yaml']);
-    repo.runGit(['commit', '-m', 'delete']);
+    // Delete the repo. This will cause "pub get" to fail if it tries to
+    // re-fetch.
+    schedule(() => deleteEntry(p.join(sandboxDir, 'foo.git')));
 
-    pubUpgrade(error: new RegExp(r'Could not find a file named "pubspec.yaml" '
-        r'in "[^\n]*"\.'));
+    pubGet();
 
     d.dir(packagesPath, [
       d.dir('foo', [