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

sdk/lib/_internal/pub_generated/lib/src/validator/compiled_dartdoc.dart

Index: sdk/lib/_internal/pub_generated/lib/src/validator/compiled_dartdoc.dart
diff --git a/sdk/lib/_internal/pub_generated/lib/src/validator/compiled_dartdoc.dart b/sdk/lib/_internal/pub_generated/lib/src/validator/compiled_dartdoc.dart
new file mode 100644
index 0000000000000000000000000000000000000000..3dc88b4a0e3702c89c274a05b0704439601e878b
--- /dev/null
+++ b/sdk/lib/_internal/pub_generated/lib/src/validator/compiled_dartdoc.dart
@@ -0,0 +1,29 @@
+library pub.validator.compiled_dartdoc;
+import 'dart:async';
+import 'package:path/path.dart' as path;
+import '../entrypoint.dart';
+import '../io.dart';
+import '../utils.dart';
+import '../validator.dart';
+class CompiledDartdocValidator extends Validator {
+  CompiledDartdocValidator(Entrypoint entrypoint) : super(entrypoint);
+  Future validate() {
+    return syncFuture(() {
+      for (var entry in entrypoint.root.listFiles()) {
+        if (path.basename(entry) != "nav.json") continue;
+        var dir = path.dirname(entry);
+        var files = [
+            entry,
+            path.join(dir, "index.html"),
+            path.join(dir, "styles.css"),
+            path.join(dir, "dart-logo-small.png"),
+            path.join(dir, "client-live-nav.js")];
+        if (files.every((val) => fileExists(val))) {
+          warnings.add(
+              "Avoid putting generated documentation in " "${path.relative(dir)}.\n"
+                  "Generated documentation bloats the package with redundant " "data.");
+        }
+      }
+    });
+  }
+}