Store the async-await compiled pub code directly in the repo.

sdk/lib/_internal/pub_generated/test/global/activate/snapshots_git_executables_test.dart

+import 'package:scheduled_test/scheduled_test.dart';
+import '../../descriptor.dart' as d;
+import '../../test_pub.dart';
+main() {
+  initConfig();
+  integration('snapshots the executables for a Git repo', () {
+    ensureGit();
+    d.git(
+        'foo.git',
+        [
+            d.libPubspec("foo", "1.0.0"),
+            d.dir(
+                "bin",
+                [
+                    d.file("hello.dart", "void main() => print('hello!');"),
+                    d.file("goodbye.dart", "void main() => print('goodbye!');"),
+                    d.file("shell.sh", "echo shell"),
+                    d.dir(
+                        "subdir",
+                        [d.file("sub.dart", "void main() => print('sub!');")])])]).create();
+    schedulePub(
+        args: ["global", "activate", "-sgit", "../foo.git"],
+        output: allOf(
+            [contains('Precompiled foo:hello.'), contains("Precompiled foo:goodbye.")]));
+    d.dir(
+        cachePath,
+        [
+            d.dir(
+                'global_packages',
+                [
+                    d.dir(
+                        'foo',
+                        [
+                            d.matcherFile('pubspec.lock', contains('1.0.0')),
+                            d.dir(
+                                'bin',
+                                [
+                                    d.matcherFile('hello.dart.snapshot', contains('hello!')),
+                                    d.matcherFile('goodbye.dart.snapshot', contains('goodbye!')),
+                                    d.nothing('shell.sh.snapshot'),
+                                    d.nothing('subdir')])])])]).validate();
+  });
+}