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

sdk/lib/_internal/pub_generated/test/get/hosted/get_test.dart

+library pub_tests;
+import '../../../lib/src/exit_codes.dart' as exit_codes;
+import '../../descriptor.dart' as d;
+import '../../test_pub.dart';
+main() {
+  initConfig();
+  integration('gets a package from a pub server', () {
+    servePackages((builder) => builder.serve("foo", "1.2.3"));
+    d.appDir({
+      "foo": "1.2.3"
+    }).create();
+    pubGet();
+    d.cacheDir({
+      "foo": "1.2.3"
+    }).validate();
+    d.packagesDir({
+      "foo": "1.2.3"
+    }).validate();
+  });
+  integration('URL encodes the package name', () {
+    serveNoPackages();
+    d.appDir({
+      "bad name!": "1.2.3"
+    }).create();
+    pubGet(
+        error: new RegExp(
+            r"Could not find package bad name! at http://localhost:\d+\."),
+        exitCode: exit_codes.UNAVAILABLE);
+  });
+}