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

sdk/lib/_internal/pub/test/cache/repair/handles_corrupted_binstub_test.dart

Index: sdk/lib/_internal/pub/test/cache/repair/handles_corrupted_binstub_test.dart
diff --git a/sdk/lib/_internal/pub/test/global/binstubs/binstub_runs_precompiled_snapshot_test.dart b/sdk/lib/_internal/pub/test/cache/repair/handles_corrupted_binstub_test.dart
similarity index 62%
copy from sdk/lib/_internal/pub/test/global/binstubs/binstub_runs_precompiled_snapshot_test.dart
copy to sdk/lib/_internal/pub/test/cache/repair/handles_corrupted_binstub_test.dart
index 3d704e73edb02ecbecdc157043ff0121037fbe16..5af3b4703f3cca5ba4eaf1f3c8200a7a244e428a 100644
--- a/sdk/lib/_internal/pub/test/global/binstubs/binstub_runs_precompiled_snapshot_test.dart
+++ b/sdk/lib/_internal/pub/test/cache/repair/handles_corrupted_binstub_test.dart
@@ -2,21 +2,20 @@
 // 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 'dart:io';
+
 import 'package:scheduled_test/scheduled_test.dart';
 
 import '../../descriptor.dart' as d;
 import '../../test_pub.dart';
-import 'utils.dart';
 
 main() {
   initConfig();
-  integration("the binstubs runs a precompiled snapshot if present", () {
+  integration('handles a corrupted binstub script', () {
     servePackages((builder) {
-      builder.serve("foo", "1.0.0", pubspec: {
-        "executables": {
-          "foo-script": "script"
-        }
-      }, contents: [
+      builder.serve("foo", "1.0.0", contents: [
         d.dir("bin", [
           d.file("script.dart", "main(args) => print('ok');")
         ])
@@ -26,10 +25,12 @@ main() {
     schedulePub(args: ["global", "activate", "foo"]);
 
     d.dir(cachePath, [
-      d.dir("bin", [
-        d.matcherFile(binStubName("foo-script"),
-            contains("script.dart.snapshot"))
+      d.dir('bin', [
+        d.file(binStubName('script'), 'junk')
       ])
-    ]).validate();
+    ]).create();
+
+    schedulePub(args: ["cache", "repair"],
+        error: contains('Error reading binstub for "script":'));
   });
 }