CFE disallows the re-exported use of Record class in legacy libraries

[chloestefantsova]

The following example should be accepted by the CFE.

// asdf_lib.dart
export 'dart:core' show Record;

// asdf.dart
import './asdf_lib.dart';

Record foo() => throw 0;

[chloestefantsova]

The requirement for the visibility of Record has changed, and now it should be visible in the legacy programs, imported directly or indirectly, if the experiment is enabled for the entire program: #50317 (comment)