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

sdk/lib/_internal/pub_generated/test/run/errors_if_only_transitive_dependency_test.dart

+import '../../lib/src/exit_codes.dart' as exit_codes;
+import '../descriptor.dart' as d;
+import '../test_pub.dart';
+main() {
+  initConfig();
+  integration('Errors if the script is in a non-immediate dependency.', () {
+    d.dir(
+        "foo",
+        [
+            d.libPubspec("foo", "1.0.0"),
+            d.dir("bin", [d.file("bar.dart", "main() => print('foobar');")])]).create();
+    d.dir("bar", [d.libPubspec("bar", "1.0.0", deps: {
+        "foo": {
+          "path": "../foo"
+        }
+      })]).create();
+    d.dir(appPath, [d.appPubspec({
+        "bar": {
+          "path": "../bar"
+        }
+      })]).create();
+    pubGet();
+    var pub = pubRun(args: ["foo:script"]);
+    pub.stderr.expect('Package "foo" is not an immediate dependency.');
+    pub.stderr.expect('Cannot run executables in transitive dependencies.');
+    pub.shouldExit(exit_codes.DATA);
+  });
+}