Found in #179089

Running flutter analyze --flutter-repo did not run analysis over engine/src/flutter
Found many many failures in CI after pushing the PR: https://logs.chromium.org/logs/flutter/buildbucket/cr-buildbucket/8697209365795429281/+/u/test:_analyze_dart_ui/stdout