Precompile immutable globally-installed pub executables.

sdk/lib/_internal/pub/test/global/activate/uncached_package_test.dart

 // 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.
 
 import 'package:scheduled_test/scheduled_test.dart';
 
 import '../../descriptor.dart' as d;
 import '../../test_pub.dart';
 
 main() {
   initConfig();
   integration('installs and activates the best version of a package', () {
     servePackages((builder) {
       builder.serve("foo", "1.0.0");
       builder.serve("foo", "1.2.3");
       builder.serve("foo", "2.0.0-wildly.unstable");
     });
 
     schedulePub(args: ["global", "activate", "foo"], output: """
         Resolving dependencies...
         + foo 1.2.3 (2.0.0-wildly.unstable available)
         Downloading foo 1.2.3...
+        Precompiling executables...
+        Loading source assets...
         Activated foo 1.2.3.""");
 
     // Should be in global package cache.
     d.dir(cachePath, [
       d.dir('global_packages', [
-        d.matcherFile('foo.lock', contains('1.2.3'))
+        d.dir('foo', [d.matcherFile('pubspec.lock', contains('1.2.3'))])
       ])
     ]).validate();
   });
 }