We removed support or IE11 and old Edge, but we still have the FontFace polyfills for them: https://github.com/flutter/engine/blob/5f88ee42b1c3740772256735cea2a39c6c5aed0d/lib/web_ui/lib/src/engine/text/font_collection.dart#L249

We should clean them up.