The withWeakReferenceTo allows encapsulating class to be garbage collected has started failing consistently in the webview_flutter_wkwebview integration test. It is failing on post-submit, but didn't fail in the presubmit.

I wasn't able to reproduce the failure locally either on flutter/flutter 034aa2f760d4d5e24fa11bed1839a9cccb297d21.

See https://logs.chromium.org/logs/flutter/buildbucket/cr-buildbucket/8747939904016287009/+/u/Run_package_tests/drive_examples/stdout