Make pub's binstubs resilient to changes in snapshot format.

sdk/lib/_internal/pub_generated/test/cache/repair/recompiles_snapshots_test.dart

Index: sdk/lib/_internal/pub_generated/test/cache/repair/recompiles_snapshots_test.dart
diff --git a/sdk/lib/_internal/pub_generated/test/global/run/runs_script_test.dart b/sdk/lib/_internal/pub_generated/test/cache/repair/recompiles_snapshots_test.dart
similarity index 52%
copy from sdk/lib/_internal/pub_generated/test/global/run/runs_script_test.dart
copy to sdk/lib/_internal/pub_generated/test/cache/repair/recompiles_snapshots_test.dart
index 3d9f35cb42df25128aee1dd25f5f8bf491e06e7c..499f3ced47659af19621469c41751621fc4bff30 100644
--- a/sdk/lib/_internal/pub_generated/test/global/run/runs_script_test.dart
+++ b/sdk/lib/_internal/pub_generated/test/cache/repair/recompiles_snapshots_test.dart
@@ -2,12 +2,16 @@
 // 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:scheduled_test/scheduled_test.dart';
+
 import '../../descriptor.dart' as d;
 import '../../test_pub.dart';
 
 main() {
   initConfig();
-  integration('runs a script in an activated package', () {
+  integration('updates an outdated binstub script', () {
     servePackages((builder) {
       builder.serve(
           "foo",
@@ -18,6 +22,22 @@ main() {
 
     schedulePub(args: ["global", "activate", "foo"]);
 
+    d.dir(
+        cachePath,
+        [
+            d.dir(
+                'global_packages/foo/bin',
+                [d.file('script.dart.snapshot', 'junk')])]).create();
+
+    schedulePub(args: ["cache", "repair"], output: '''
+          Downloading foo 1.0.0...
+          Reinstalled 1 package.
+          Reactivating foo 1.0.0...
+          Precompiling executables...
+          Loading source assets...
+          Precompiled foo:script.
+          Reactivated 1 package.''');
+
     var pub = pubRun(global: true, args: ["foo:script"]);
     pub.stdout.expect("ok");
     pub.shouldExit();