CLI support for embedders (#25380).

pkg/analyzer_cli/test/data/package_with_embedder_yaml/lib/grizzly.dart

Index: pkg/analyzer_cli/test/data/package_with_embedder_yaml/lib/grizzly.dart
diff --git a/tests/language/export_not_shadowed_by_prefix_helper2.dart b/pkg/analyzer_cli/test/data/package_with_embedder_yaml/lib/grizzly.dart
similarity index 79%
copy from tests/language/export_not_shadowed_by_prefix_helper2.dart
copy to pkg/analyzer_cli/test/data/package_with_embedder_yaml/lib/grizzly.dart
index ae2dca5fcf0a4842b29e20d7652b35b6bfd65cfc..d575643598c26036bc0e72a3592eeccc5d6eaf44 100644
--- a/tests/language/export_not_shadowed_by_prefix_helper2.dart
+++ b/pkg/analyzer_cli/test/data/package_with_embedder_yaml/lib/grizzly.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-void f() {
-  f_called = true;
-}
+library grizzly;
 
-bool f_called = false;
+class Bear {}