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

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

Index: sdk/lib/_internal/pub_generated/lib/src/validator/size.dart
diff --git a/sdk/lib/_internal/pub_generated/lib/src/validator/size.dart b/sdk/lib/_internal/pub_generated/lib/src/validator/size.dart
new file mode 100644
index 0000000000000000000000000000000000000000..675587c5e5796b2345fd2b2a1e8e891763d0a1e3
--- /dev/null
+++ b/sdk/lib/_internal/pub_generated/lib/src/validator/size.dart
@@ -0,0 +1,18 @@
+library pub.validator.size;
+import 'dart:async';
+import 'dart:math' as math;
+import '../entrypoint.dart';
+import '../validator.dart';
+const _MAX_SIZE = 10 * 1024 * 1024;
+class SizeValidator extends Validator {
+  final Future<int> packageSize;
+  SizeValidator(Entrypoint entrypoint, this.packageSize) : super(entrypoint);
+  Future validate() {
+    return packageSize.then((size) {
+      if (size <= _MAX_SIZE) return;
+      var sizeInMb = (size / math.pow(2, 20)).toStringAsPrecision(4);
+      errors.add(
+          "Your package is $sizeInMb MB. Hosted packages must be " "smaller than 10 MB.");
+    });
+  }
+}